diff --git "a/\344\275\231\344\277\212\347\207\225/7.1\344\275\234\344\270\232/app/dist/bda0da14b39bd2ca2d44.jpg" "b/\344\275\231\344\277\212\347\207\225/7.1\344\275\234\344\270\232/app/dist/bda0da14b39bd2ca2d44.jpg" new file mode 100644 index 0000000000000000000000000000000000000000..28889e1c3f08a15a1c79e8e6d995ac60ff1fe3de Binary files /dev/null and "b/\344\275\231\344\277\212\347\207\225/7.1\344\275\234\344\270\232/app/dist/bda0da14b39bd2ca2d44.jpg" differ diff --git "a/\344\275\231\344\277\212\347\207\225/7.1\344\275\234\344\270\232/app/dist/index.html" "b/\344\275\231\344\277\212\347\207\225/7.1\344\275\234\344\270\232/app/dist/index.html" new file mode 100644 index 0000000000000000000000000000000000000000..191e429707320ff34dbdfe809d8796d9d4073e34 --- /dev/null +++ "b/\344\275\231\344\277\212\347\207\225/7.1\344\275\234\344\270\232/app/dist/index.html" @@ -0,0 +1,10 @@ + + +
+ +' + func(text) + '
';\n * });\n *\n * p('fred, barney, & pebbles');\n * // => 'fred, barney, & pebbles
'\n */\n function wrap(value, wrapper) {\n return partial(castFunction(wrapper), value);\n }\n\n /*------------------------------------------------------------------------*/\n\n /**\n * Casts `value` as an array if it's not one.\n *\n * @static\n * @memberOf _\n * @since 4.4.0\n * @category Lang\n * @param {*} value The value to inspect.\n * @returns {Array} Returns the cast array.\n * @example\n *\n * _.castArray(1);\n * // => [1]\n *\n * _.castArray({ 'a': 1 });\n * // => [{ 'a': 1 }]\n *\n * _.castArray('abc');\n * // => ['abc']\n *\n * _.castArray(null);\n * // => [null]\n *\n * _.castArray(undefined);\n * // => [undefined]\n *\n * _.castArray();\n * // => []\n *\n * var array = [1, 2, 3];\n * console.log(_.castArray(array) === array);\n * // => true\n */\n function castArray() {\n if (!arguments.length) {\n return [];\n }\n var value = arguments[0];\n return isArray(value) ? value : [value];\n }\n\n /**\n * Creates a shallow clone of `value`.\n *\n * **Note:** This method is loosely based on the\n * [structured clone algorithm](https://mdn.io/Structured_clone_algorithm)\n * and supports cloning arrays, array buffers, booleans, date objects, maps,\n * numbers, `Object` objects, regexes, sets, strings, symbols, and typed\n * arrays. The own enumerable properties of `arguments` objects are cloned\n * as plain objects. An empty object is returned for uncloneable values such\n * as error objects, functions, DOM nodes, and WeakMaps.\n *\n * @static\n * @memberOf _\n * @since 0.1.0\n * @category Lang\n * @param {*} value The value to clone.\n * @returns {*} Returns the cloned value.\n * @see _.cloneDeep\n * @example\n *\n * var objects = [{ 'a': 1 }, { 'b': 2 }];\n *\n * var shallow = _.clone(objects);\n * console.log(shallow[0] === objects[0]);\n * // => true\n */\n function clone(value) {\n return baseClone(value, CLONE_SYMBOLS_FLAG);\n }\n\n /**\n * This method is like `_.clone` except that it accepts `customizer` which\n * is invoked to produce the cloned value. If `customizer` returns `undefined`,\n * cloning is handled by the method instead. The `customizer` is invoked with\n * up to four arguments; (value [, index|key, object, stack]).\n *\n * @static\n * @memberOf _\n * @since 4.0.0\n * @category Lang\n * @param {*} value The value to clone.\n * @param {Function} [customizer] The function to customize cloning.\n * @returns {*} Returns the cloned value.\n * @see _.cloneDeepWith\n * @example\n *\n * function customizer(value) {\n * if (_.isElement(value)) {\n * return value.cloneNode(false);\n * }\n * }\n *\n * var el = _.cloneWith(document.body, customizer);\n *\n * console.log(el === document.body);\n * // => false\n * console.log(el.nodeName);\n * // => 'BODY'\n * console.log(el.childNodes.length);\n * // => 0\n */\n function cloneWith(value, customizer) {\n customizer = typeof customizer == 'function' ? customizer : undefined;\n return baseClone(value, CLONE_SYMBOLS_FLAG, customizer);\n }\n\n /**\n * This method is like `_.clone` except that it recursively clones `value`.\n *\n * @static\n * @memberOf _\n * @since 1.0.0\n * @category Lang\n * @param {*} value The value to recursively clone.\n * @returns {*} Returns the deep cloned value.\n * @see _.clone\n * @example\n *\n * var objects = [{ 'a': 1 }, { 'b': 2 }];\n *\n * var deep = _.cloneDeep(objects);\n * console.log(deep[0] === objects[0]);\n * // => false\n */\n function cloneDeep(value) {\n return baseClone(value, CLONE_DEEP_FLAG | CLONE_SYMBOLS_FLAG);\n }\n\n /**\n * This method is like `_.cloneWith` except that it recursively clones `value`.\n *\n * @static\n * @memberOf _\n * @since 4.0.0\n * @category Lang\n * @param {*} value The value to recursively clone.\n * @param {Function} [customizer] The function to customize cloning.\n * @returns {*} Returns the deep cloned value.\n * @see _.cloneWith\n * @example\n *\n * function customizer(value) {\n * if (_.isElement(value)) {\n * return value.cloneNode(true);\n * }\n * }\n *\n * var el = _.cloneDeepWith(document.body, customizer);\n *\n * console.log(el === document.body);\n * // => false\n * console.log(el.nodeName);\n * // => 'BODY'\n * console.log(el.childNodes.length);\n * // => 20\n */\n function cloneDeepWith(value, customizer) {\n customizer = typeof customizer == 'function' ? customizer : undefined;\n return baseClone(value, CLONE_DEEP_FLAG | CLONE_SYMBOLS_FLAG, customizer);\n }\n\n /**\n * Checks if `object` conforms to `source` by invoking the predicate\n * properties of `source` with the corresponding property values of `object`.\n *\n * **Note:** This method is equivalent to `_.conforms` when `source` is\n * partially applied.\n *\n * @static\n * @memberOf _\n * @since 4.14.0\n * @category Lang\n * @param {Object} object The object to inspect.\n * @param {Object} source The object of property predicates to conform to.\n * @returns {boolean} Returns `true` if `object` conforms, else `false`.\n * @example\n *\n * var object = { 'a': 1, 'b': 2 };\n *\n * _.conformsTo(object, { 'b': function(n) { return n > 1; } });\n * // => true\n *\n * _.conformsTo(object, { 'b': function(n) { return n > 2; } });\n * // => false\n */\n function conformsTo(object, source) {\n return source == null || baseConformsTo(object, source, keys(source));\n }\n\n /**\n * Performs a\n * [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero)\n * comparison between two values to determine if they are equivalent.\n *\n * @static\n * @memberOf _\n * @since 4.0.0\n * @category Lang\n * @param {*} value The value to compare.\n * @param {*} other The other value to compare.\n * @returns {boolean} Returns `true` if the values are equivalent, else `false`.\n * @example\n *\n * var object = { 'a': 1 };\n * var other = { 'a': 1 };\n *\n * _.eq(object, object);\n * // => true\n *\n * _.eq(object, other);\n * // => false\n *\n * _.eq('a', 'a');\n * // => true\n *\n * _.eq('a', Object('a'));\n * // => false\n *\n * _.eq(NaN, NaN);\n * // => true\n */\n function eq(value, other) {\n return value === other || (value !== value && other !== other);\n }\n\n /**\n * Checks if `value` is greater than `other`.\n *\n * @static\n * @memberOf _\n * @since 3.9.0\n * @category Lang\n * @param {*} value The value to compare.\n * @param {*} other The other value to compare.\n * @returns {boolean} Returns `true` if `value` is greater than `other`,\n * else `false`.\n * @see _.lt\n * @example\n *\n * _.gt(3, 1);\n * // => true\n *\n * _.gt(3, 3);\n * // => false\n *\n * _.gt(1, 3);\n * // => false\n */\n var gt = createRelationalOperation(baseGt);\n\n /**\n * Checks if `value` is greater than or equal to `other`.\n *\n * @static\n * @memberOf _\n * @since 3.9.0\n * @category Lang\n * @param {*} value The value to compare.\n * @param {*} other The other value to compare.\n * @returns {boolean} Returns `true` if `value` is greater than or equal to\n * `other`, else `false`.\n * @see _.lte\n * @example\n *\n * _.gte(3, 1);\n * // => true\n *\n * _.gte(3, 3);\n * // => true\n *\n * _.gte(1, 3);\n * // => false\n */\n var gte = createRelationalOperation(function(value, other) {\n return value >= other;\n });\n\n /**\n * Checks if `value` is likely an `arguments` object.\n *\n * @static\n * @memberOf _\n * @since 0.1.0\n * @category Lang\n * @param {*} value The value to check.\n * @returns {boolean} Returns `true` if `value` is an `arguments` object,\n * else `false`.\n * @example\n *\n * _.isArguments(function() { return arguments; }());\n * // => true\n *\n * _.isArguments([1, 2, 3]);\n * // => false\n */\n var isArguments = baseIsArguments(function() { return arguments; }()) ? baseIsArguments : function(value) {\n return isObjectLike(value) && hasOwnProperty.call(value, 'callee') &&\n !propertyIsEnumerable.call(value, 'callee');\n };\n\n /**\n * Checks if `value` is classified as an `Array` object.\n *\n * @static\n * @memberOf _\n * @since 0.1.0\n * @category Lang\n * @param {*} value The value to check.\n * @returns {boolean} Returns `true` if `value` is an array, else `false`.\n * @example\n *\n * _.isArray([1, 2, 3]);\n * // => true\n *\n * _.isArray(document.body.children);\n * // => false\n *\n * _.isArray('abc');\n * // => false\n *\n * _.isArray(_.noop);\n * // => false\n */\n var isArray = Array.isArray;\n\n /**\n * Checks if `value` is classified as an `ArrayBuffer` object.\n *\n * @static\n * @memberOf _\n * @since 4.3.0\n * @category Lang\n * @param {*} value The value to check.\n * @returns {boolean} Returns `true` if `value` is an array buffer, else `false`.\n * @example\n *\n * _.isArrayBuffer(new ArrayBuffer(2));\n * // => true\n *\n * _.isArrayBuffer(new Array(2));\n * // => false\n */\n var isArrayBuffer = nodeIsArrayBuffer ? baseUnary(nodeIsArrayBuffer) : baseIsArrayBuffer;\n\n /**\n * Checks if `value` is array-like. A value is considered array-like if it's\n * not a function and has a `value.length` that's an integer greater than or\n * equal to `0` and less than or equal to `Number.MAX_SAFE_INTEGER`.\n *\n * @static\n * @memberOf _\n * @since 4.0.0\n * @category Lang\n * @param {*} value The value to check.\n * @returns {boolean} Returns `true` if `value` is array-like, else `false`.\n * @example\n *\n * _.isArrayLike([1, 2, 3]);\n * // => true\n *\n * _.isArrayLike(document.body.children);\n * // => true\n *\n * _.isArrayLike('abc');\n * // => true\n *\n * _.isArrayLike(_.noop);\n * // => false\n */\n function isArrayLike(value) {\n return value != null && isLength(value.length) && !isFunction(value);\n }\n\n /**\n * This method is like `_.isArrayLike` except that it also checks if `value`\n * is an object.\n *\n * @static\n * @memberOf _\n * @since 4.0.0\n * @category Lang\n * @param {*} value The value to check.\n * @returns {boolean} Returns `true` if `value` is an array-like object,\n * else `false`.\n * @example\n *\n * _.isArrayLikeObject([1, 2, 3]);\n * // => true\n *\n * _.isArrayLikeObject(document.body.children);\n * // => true\n *\n * _.isArrayLikeObject('abc');\n * // => false\n *\n * _.isArrayLikeObject(_.noop);\n * // => false\n */\n function isArrayLikeObject(value) {\n return isObjectLike(value) && isArrayLike(value);\n }\n\n /**\n * Checks if `value` is classified as a boolean primitive or object.\n *\n * @static\n * @memberOf _\n * @since 0.1.0\n * @category Lang\n * @param {*} value The value to check.\n * @returns {boolean} Returns `true` if `value` is a boolean, else `false`.\n * @example\n *\n * _.isBoolean(false);\n * // => true\n *\n * _.isBoolean(null);\n * // => false\n */\n function isBoolean(value) {\n return value === true || value === false ||\n (isObjectLike(value) && baseGetTag(value) == boolTag);\n }\n\n /**\n * Checks if `value` is a buffer.\n *\n * @static\n * @memberOf _\n * @since 4.3.0\n * @category Lang\n * @param {*} value The value to check.\n * @returns {boolean} Returns `true` if `value` is a buffer, else `false`.\n * @example\n *\n * _.isBuffer(new Buffer(2));\n * // => true\n *\n * _.isBuffer(new Uint8Array(2));\n * // => false\n */\n var isBuffer = nativeIsBuffer || stubFalse;\n\n /**\n * Checks if `value` is classified as a `Date` object.\n *\n * @static\n * @memberOf _\n * @since 0.1.0\n * @category Lang\n * @param {*} value The value to check.\n * @returns {boolean} Returns `true` if `value` is a date object, else `false`.\n * @example\n *\n * _.isDate(new Date);\n * // => true\n *\n * _.isDate('Mon April 23 2012');\n * // => false\n */\n var isDate = nodeIsDate ? baseUnary(nodeIsDate) : baseIsDate;\n\n /**\n * Checks if `value` is likely a DOM element.\n *\n * @static\n * @memberOf _\n * @since 0.1.0\n * @category Lang\n * @param {*} value The value to check.\n * @returns {boolean} Returns `true` if `value` is a DOM element, else `false`.\n * @example\n *\n * _.isElement(document.body);\n * // => true\n *\n * _.isElement('');\n * // => false\n */\n function isElement(value) {\n return isObjectLike(value) && value.nodeType === 1 && !isPlainObject(value);\n }\n\n /**\n * Checks if `value` is an empty object, collection, map, or set.\n *\n * Objects are considered empty if they have no own enumerable string keyed\n * properties.\n *\n * Array-like values such as `arguments` objects, arrays, buffers, strings, or\n * jQuery-like collections are considered empty if they have a `length` of `0`.\n * Similarly, maps and sets are considered empty if they have a `size` of `0`.\n *\n * @static\n * @memberOf _\n * @since 0.1.0\n * @category Lang\n * @param {*} value The value to check.\n * @returns {boolean} Returns `true` if `value` is empty, else `false`.\n * @example\n *\n * _.isEmpty(null);\n * // => true\n *\n * _.isEmpty(true);\n * // => true\n *\n * _.isEmpty(1);\n * // => true\n *\n * _.isEmpty([1, 2, 3]);\n * // => false\n *\n * _.isEmpty({ 'a': 1 });\n * // => false\n */\n function isEmpty(value) {\n if (value == null) {\n return true;\n }\n if (isArrayLike(value) &&\n (isArray(value) || typeof value == 'string' || typeof value.splice == 'function' ||\n isBuffer(value) || isTypedArray(value) || isArguments(value))) {\n return !value.length;\n }\n var tag = getTag(value);\n if (tag == mapTag || tag == setTag) {\n return !value.size;\n }\n if (isPrototype(value)) {\n return !baseKeys(value).length;\n }\n for (var key in value) {\n if (hasOwnProperty.call(value, key)) {\n return false;\n }\n }\n return true;\n }\n\n /**\n * Performs a deep comparison between two values to determine if they are\n * equivalent.\n *\n * **Note:** This method supports comparing arrays, array buffers, booleans,\n * date objects, error objects, maps, numbers, `Object` objects, regexes,\n * sets, strings, symbols, and typed arrays. `Object` objects are compared\n * by their own, not inherited, enumerable properties. Functions and DOM\n * nodes are compared by strict equality, i.e. `===`.\n *\n * @static\n * @memberOf _\n * @since 0.1.0\n * @category Lang\n * @param {*} value The value to compare.\n * @param {*} other The other value to compare.\n * @returns {boolean} Returns `true` if the values are equivalent, else `false`.\n * @example\n *\n * var object = { 'a': 1 };\n * var other = { 'a': 1 };\n *\n * _.isEqual(object, other);\n * // => true\n *\n * object === other;\n * // => false\n */\n function isEqual(value, other) {\n return baseIsEqual(value, other);\n }\n\n /**\n * This method is like `_.isEqual` except that it accepts `customizer` which\n * is invoked to compare values. If `customizer` returns `undefined`, comparisons\n * are handled by the method instead. The `customizer` is invoked with up to\n * six arguments: (objValue, othValue [, index|key, object, other, stack]).\n *\n * @static\n * @memberOf _\n * @since 4.0.0\n * @category Lang\n * @param {*} value The value to compare.\n * @param {*} other The other value to compare.\n * @param {Function} [customizer] The function to customize comparisons.\n * @returns {boolean} Returns `true` if the values are equivalent, else `false`.\n * @example\n *\n * function isGreeting(value) {\n * return /^h(?:i|ello)$/.test(value);\n * }\n *\n * function customizer(objValue, othValue) {\n * if (isGreeting(objValue) && isGreeting(othValue)) {\n * return true;\n * }\n * }\n *\n * var array = ['hello', 'goodbye'];\n * var other = ['hi', 'goodbye'];\n *\n * _.isEqualWith(array, other, customizer);\n * // => true\n */\n function isEqualWith(value, other, customizer) {\n customizer = typeof customizer == 'function' ? customizer : undefined;\n var result = customizer ? customizer(value, other) : undefined;\n return result === undefined ? baseIsEqual(value, other, undefined, customizer) : !!result;\n }\n\n /**\n * Checks if `value` is an `Error`, `EvalError`, `RangeError`, `ReferenceError`,\n * `SyntaxError`, `TypeError`, or `URIError` object.\n *\n * @static\n * @memberOf _\n * @since 3.0.0\n * @category Lang\n * @param {*} value The value to check.\n * @returns {boolean} Returns `true` if `value` is an error object, else `false`.\n * @example\n *\n * _.isError(new Error);\n * // => true\n *\n * _.isError(Error);\n * // => false\n */\n function isError(value) {\n if (!isObjectLike(value)) {\n return false;\n }\n var tag = baseGetTag(value);\n return tag == errorTag || tag == domExcTag ||\n (typeof value.message == 'string' && typeof value.name == 'string' && !isPlainObject(value));\n }\n\n /**\n * Checks if `value` is a finite primitive number.\n *\n * **Note:** This method is based on\n * [`Number.isFinite`](https://mdn.io/Number/isFinite).\n *\n * @static\n * @memberOf _\n * @since 0.1.0\n * @category Lang\n * @param {*} value The value to check.\n * @returns {boolean} Returns `true` if `value` is a finite number, else `false`.\n * @example\n *\n * _.isFinite(3);\n * // => true\n *\n * _.isFinite(Number.MIN_VALUE);\n * // => true\n *\n * _.isFinite(Infinity);\n * // => false\n *\n * _.isFinite('3');\n * // => false\n */\n function isFinite(value) {\n return typeof value == 'number' && nativeIsFinite(value);\n }\n\n /**\n * Checks if `value` is classified as a `Function` object.\n *\n * @static\n * @memberOf _\n * @since 0.1.0\n * @category Lang\n * @param {*} value The value to check.\n * @returns {boolean} Returns `true` if `value` is a function, else `false`.\n * @example\n *\n * _.isFunction(_);\n * // => true\n *\n * _.isFunction(/abc/);\n * // => false\n */\n function isFunction(value) {\n if (!isObject(value)) {\n return false;\n }\n // The use of `Object#toString` avoids issues with the `typeof` operator\n // in Safari 9 which returns 'object' for typed arrays and other constructors.\n var tag = baseGetTag(value);\n return tag == funcTag || tag == genTag || tag == asyncTag || tag == proxyTag;\n }\n\n /**\n * Checks if `value` is an integer.\n *\n * **Note:** This method is based on\n * [`Number.isInteger`](https://mdn.io/Number/isInteger).\n *\n * @static\n * @memberOf _\n * @since 4.0.0\n * @category Lang\n * @param {*} value The value to check.\n * @returns {boolean} Returns `true` if `value` is an integer, else `false`.\n * @example\n *\n * _.isInteger(3);\n * // => true\n *\n * _.isInteger(Number.MIN_VALUE);\n * // => false\n *\n * _.isInteger(Infinity);\n * // => false\n *\n * _.isInteger('3');\n * // => false\n */\n function isInteger(value) {\n return typeof value == 'number' && value == toInteger(value);\n }\n\n /**\n * Checks if `value` is a valid array-like length.\n *\n * **Note:** This method is loosely based on\n * [`ToLength`](http://ecma-international.org/ecma-262/7.0/#sec-tolength).\n *\n * @static\n * @memberOf _\n * @since 4.0.0\n * @category Lang\n * @param {*} value The value to check.\n * @returns {boolean} Returns `true` if `value` is a valid length, else `false`.\n * @example\n *\n * _.isLength(3);\n * // => true\n *\n * _.isLength(Number.MIN_VALUE);\n * // => false\n *\n * _.isLength(Infinity);\n * // => false\n *\n * _.isLength('3');\n * // => false\n */\n function isLength(value) {\n return typeof value == 'number' &&\n value > -1 && value % 1 == 0 && value <= MAX_SAFE_INTEGER;\n }\n\n /**\n * Checks if `value` is the\n * [language type](http://www.ecma-international.org/ecma-262/7.0/#sec-ecmascript-language-types)\n * of `Object`. (e.g. arrays, functions, objects, regexes, `new Number(0)`, and `new String('')`)\n *\n * @static\n * @memberOf _\n * @since 0.1.0\n * @category Lang\n * @param {*} value The value to check.\n * @returns {boolean} Returns `true` if `value` is an object, else `false`.\n * @example\n *\n * _.isObject({});\n * // => true\n *\n * _.isObject([1, 2, 3]);\n * // => true\n *\n * _.isObject(_.noop);\n * // => true\n *\n * _.isObject(null);\n * // => false\n */\n function isObject(value) {\n var type = typeof value;\n return value != null && (type == 'object' || type == 'function');\n }\n\n /**\n * Checks if `value` is object-like. A value is object-like if it's not `null`\n * and has a `typeof` result of \"object\".\n *\n * @static\n * @memberOf _\n * @since 4.0.0\n * @category Lang\n * @param {*} value The value to check.\n * @returns {boolean} Returns `true` if `value` is object-like, else `false`.\n * @example\n *\n * _.isObjectLike({});\n * // => true\n *\n * _.isObjectLike([1, 2, 3]);\n * // => true\n *\n * _.isObjectLike(_.noop);\n * // => false\n *\n * _.isObjectLike(null);\n * // => false\n */\n function isObjectLike(value) {\n return value != null && typeof value == 'object';\n }\n\n /**\n * Checks if `value` is classified as a `Map` object.\n *\n * @static\n * @memberOf _\n * @since 4.3.0\n * @category Lang\n * @param {*} value The value to check.\n * @returns {boolean} Returns `true` if `value` is a map, else `false`.\n * @example\n *\n * _.isMap(new Map);\n * // => true\n *\n * _.isMap(new WeakMap);\n * // => false\n */\n var isMap = nodeIsMap ? baseUnary(nodeIsMap) : baseIsMap;\n\n /**\n * Performs a partial deep comparison between `object` and `source` to\n * determine if `object` contains equivalent property values.\n *\n * **Note:** This method is equivalent to `_.matches` when `source` is\n * partially applied.\n *\n * Partial comparisons will match empty array and empty object `source`\n * values against any array or object value, respectively. See `_.isEqual`\n * for a list of supported value comparisons.\n *\n * @static\n * @memberOf _\n * @since 3.0.0\n * @category Lang\n * @param {Object} object The object to inspect.\n * @param {Object} source The object of property values to match.\n * @returns {boolean} Returns `true` if `object` is a match, else `false`.\n * @example\n *\n * var object = { 'a': 1, 'b': 2 };\n *\n * _.isMatch(object, { 'b': 2 });\n * // => true\n *\n * _.isMatch(object, { 'b': 1 });\n * // => false\n */\n function isMatch(object, source) {\n return object === source || baseIsMatch(object, source, getMatchData(source));\n }\n\n /**\n * This method is like `_.isMatch` except that it accepts `customizer` which\n * is invoked to compare values. If `customizer` returns `undefined`, comparisons\n * are handled by the method instead. The `customizer` is invoked with five\n * arguments: (objValue, srcValue, index|key, object, source).\n *\n * @static\n * @memberOf _\n * @since 4.0.0\n * @category Lang\n * @param {Object} object The object to inspect.\n * @param {Object} source The object of property values to match.\n * @param {Function} [customizer] The function to customize comparisons.\n * @returns {boolean} Returns `true` if `object` is a match, else `false`.\n * @example\n *\n * function isGreeting(value) {\n * return /^h(?:i|ello)$/.test(value);\n * }\n *\n * function customizer(objValue, srcValue) {\n * if (isGreeting(objValue) && isGreeting(srcValue)) {\n * return true;\n * }\n * }\n *\n * var object = { 'greeting': 'hello' };\n * var source = { 'greeting': 'hi' };\n *\n * _.isMatchWith(object, source, customizer);\n * // => true\n */\n function isMatchWith(object, source, customizer) {\n customizer = typeof customizer == 'function' ? customizer : undefined;\n return baseIsMatch(object, source, getMatchData(source), customizer);\n }\n\n /**\n * Checks if `value` is `NaN`.\n *\n * **Note:** This method is based on\n * [`Number.isNaN`](https://mdn.io/Number/isNaN) and is not the same as\n * global [`isNaN`](https://mdn.io/isNaN) which returns `true` for\n * `undefined` and other non-number values.\n *\n * @static\n * @memberOf _\n * @since 0.1.0\n * @category Lang\n * @param {*} value The value to check.\n * @returns {boolean} Returns `true` if `value` is `NaN`, else `false`.\n * @example\n *\n * _.isNaN(NaN);\n * // => true\n *\n * _.isNaN(new Number(NaN));\n * // => true\n *\n * isNaN(undefined);\n * // => true\n *\n * _.isNaN(undefined);\n * // => false\n */\n function isNaN(value) {\n // An `NaN` primitive is the only value that is not equal to itself.\n // Perform the `toStringTag` check first to avoid errors with some\n // ActiveX objects in IE.\n return isNumber(value) && value != +value;\n }\n\n /**\n * Checks if `value` is a pristine native function.\n *\n * **Note:** This method can't reliably detect native functions in the presence\n * of the core-js package because core-js circumvents this kind of detection.\n * Despite multiple requests, the core-js maintainer has made it clear: any\n * attempt to fix the detection will be obstructed. As a result, we're left\n * with little choice but to throw an error. Unfortunately, this also affects\n * packages, like [babel-polyfill](https://www.npmjs.com/package/babel-polyfill),\n * which rely on core-js.\n *\n * @static\n * @memberOf _\n * @since 3.0.0\n * @category Lang\n * @param {*} value The value to check.\n * @returns {boolean} Returns `true` if `value` is a native function,\n * else `false`.\n * @example\n *\n * _.isNative(Array.prototype.push);\n * // => true\n *\n * _.isNative(_);\n * // => false\n */\n function isNative(value) {\n if (isMaskable(value)) {\n throw new Error(CORE_ERROR_TEXT);\n }\n return baseIsNative(value);\n }\n\n /**\n * Checks if `value` is `null`.\n *\n * @static\n * @memberOf _\n * @since 0.1.0\n * @category Lang\n * @param {*} value The value to check.\n * @returns {boolean} Returns `true` if `value` is `null`, else `false`.\n * @example\n *\n * _.isNull(null);\n * // => true\n *\n * _.isNull(void 0);\n * // => false\n */\n function isNull(value) {\n return value === null;\n }\n\n /**\n * Checks if `value` is `null` or `undefined`.\n *\n * @static\n * @memberOf _\n * @since 4.0.0\n * @category Lang\n * @param {*} value The value to check.\n * @returns {boolean} Returns `true` if `value` is nullish, else `false`.\n * @example\n *\n * _.isNil(null);\n * // => true\n *\n * _.isNil(void 0);\n * // => true\n *\n * _.isNil(NaN);\n * // => false\n */\n function isNil(value) {\n return value == null;\n }\n\n /**\n * Checks if `value` is classified as a `Number` primitive or object.\n *\n * **Note:** To exclude `Infinity`, `-Infinity`, and `NaN`, which are\n * classified as numbers, use the `_.isFinite` method.\n *\n * @static\n * @memberOf _\n * @since 0.1.0\n * @category Lang\n * @param {*} value The value to check.\n * @returns {boolean} Returns `true` if `value` is a number, else `false`.\n * @example\n *\n * _.isNumber(3);\n * // => true\n *\n * _.isNumber(Number.MIN_VALUE);\n * // => true\n *\n * _.isNumber(Infinity);\n * // => true\n *\n * _.isNumber('3');\n * // => false\n */\n function isNumber(value) {\n return typeof value == 'number' ||\n (isObjectLike(value) && baseGetTag(value) == numberTag);\n }\n\n /**\n * Checks if `value` is a plain object, that is, an object created by the\n * `Object` constructor or one with a `[[Prototype]]` of `null`.\n *\n * @static\n * @memberOf _\n * @since 0.8.0\n * @category Lang\n * @param {*} value The value to check.\n * @returns {boolean} Returns `true` if `value` is a plain object, else `false`.\n * @example\n *\n * function Foo() {\n * this.a = 1;\n * }\n *\n * _.isPlainObject(new Foo);\n * // => false\n *\n * _.isPlainObject([1, 2, 3]);\n * // => false\n *\n * _.isPlainObject({ 'x': 0, 'y': 0 });\n * // => true\n *\n * _.isPlainObject(Object.create(null));\n * // => true\n */\n function isPlainObject(value) {\n if (!isObjectLike(value) || baseGetTag(value) != objectTag) {\n return false;\n }\n var proto = getPrototype(value);\n if (proto === null) {\n return true;\n }\n var Ctor = hasOwnProperty.call(proto, 'constructor') && proto.constructor;\n return typeof Ctor == 'function' && Ctor instanceof Ctor &&\n funcToString.call(Ctor) == objectCtorString;\n }\n\n /**\n * Checks if `value` is classified as a `RegExp` object.\n *\n * @static\n * @memberOf _\n * @since 0.1.0\n * @category Lang\n * @param {*} value The value to check.\n * @returns {boolean} Returns `true` if `value` is a regexp, else `false`.\n * @example\n *\n * _.isRegExp(/abc/);\n * // => true\n *\n * _.isRegExp('/abc/');\n * // => false\n */\n var isRegExp = nodeIsRegExp ? baseUnary(nodeIsRegExp) : baseIsRegExp;\n\n /**\n * Checks if `value` is a safe integer. An integer is safe if it's an IEEE-754\n * double precision number which isn't the result of a rounded unsafe integer.\n *\n * **Note:** This method is based on\n * [`Number.isSafeInteger`](https://mdn.io/Number/isSafeInteger).\n *\n * @static\n * @memberOf _\n * @since 4.0.0\n * @category Lang\n * @param {*} value The value to check.\n * @returns {boolean} Returns `true` if `value` is a safe integer, else `false`.\n * @example\n *\n * _.isSafeInteger(3);\n * // => true\n *\n * _.isSafeInteger(Number.MIN_VALUE);\n * // => false\n *\n * _.isSafeInteger(Infinity);\n * // => false\n *\n * _.isSafeInteger('3');\n * // => false\n */\n function isSafeInteger(value) {\n return isInteger(value) && value >= -MAX_SAFE_INTEGER && value <= MAX_SAFE_INTEGER;\n }\n\n /**\n * Checks if `value` is classified as a `Set` object.\n *\n * @static\n * @memberOf _\n * @since 4.3.0\n * @category Lang\n * @param {*} value The value to check.\n * @returns {boolean} Returns `true` if `value` is a set, else `false`.\n * @example\n *\n * _.isSet(new Set);\n * // => true\n *\n * _.isSet(new WeakSet);\n * // => false\n */\n var isSet = nodeIsSet ? baseUnary(nodeIsSet) : baseIsSet;\n\n /**\n * Checks if `value` is classified as a `String` primitive or object.\n *\n * @static\n * @since 0.1.0\n * @memberOf _\n * @category Lang\n * @param {*} value The value to check.\n * @returns {boolean} Returns `true` if `value` is a string, else `false`.\n * @example\n *\n * _.isString('abc');\n * // => true\n *\n * _.isString(1);\n * // => false\n */\n function isString(value) {\n return typeof value == 'string' ||\n (!isArray(value) && isObjectLike(value) && baseGetTag(value) == stringTag);\n }\n\n /**\n * Checks if `value` is classified as a `Symbol` primitive or object.\n *\n * @static\n * @memberOf _\n * @since 4.0.0\n * @category Lang\n * @param {*} value The value to check.\n * @returns {boolean} Returns `true` if `value` is a symbol, else `false`.\n * @example\n *\n * _.isSymbol(Symbol.iterator);\n * // => true\n *\n * _.isSymbol('abc');\n * // => false\n */\n function isSymbol(value) {\n return typeof value == 'symbol' ||\n (isObjectLike(value) && baseGetTag(value) == symbolTag);\n }\n\n /**\n * Checks if `value` is classified as a typed array.\n *\n * @static\n * @memberOf _\n * @since 3.0.0\n * @category Lang\n * @param {*} value The value to check.\n * @returns {boolean} Returns `true` if `value` is a typed array, else `false`.\n * @example\n *\n * _.isTypedArray(new Uint8Array);\n * // => true\n *\n * _.isTypedArray([]);\n * // => false\n */\n var isTypedArray = nodeIsTypedArray ? baseUnary(nodeIsTypedArray) : baseIsTypedArray;\n\n /**\n * Checks if `value` is `undefined`.\n *\n * @static\n * @since 0.1.0\n * @memberOf _\n * @category Lang\n * @param {*} value The value to check.\n * @returns {boolean} Returns `true` if `value` is `undefined`, else `false`.\n * @example\n *\n * _.isUndefined(void 0);\n * // => true\n *\n * _.isUndefined(null);\n * // => false\n */\n function isUndefined(value) {\n return value === undefined;\n }\n\n /**\n * Checks if `value` is classified as a `WeakMap` object.\n *\n * @static\n * @memberOf _\n * @since 4.3.0\n * @category Lang\n * @param {*} value The value to check.\n * @returns {boolean} Returns `true` if `value` is a weak map, else `false`.\n * @example\n *\n * _.isWeakMap(new WeakMap);\n * // => true\n *\n * _.isWeakMap(new Map);\n * // => false\n */\n function isWeakMap(value) {\n return isObjectLike(value) && getTag(value) == weakMapTag;\n }\n\n /**\n * Checks if `value` is classified as a `WeakSet` object.\n *\n * @static\n * @memberOf _\n * @since 4.3.0\n * @category Lang\n * @param {*} value The value to check.\n * @returns {boolean} Returns `true` if `value` is a weak set, else `false`.\n * @example\n *\n * _.isWeakSet(new WeakSet);\n * // => true\n *\n * _.isWeakSet(new Set);\n * // => false\n */\n function isWeakSet(value) {\n return isObjectLike(value) && baseGetTag(value) == weakSetTag;\n }\n\n /**\n * Checks if `value` is less than `other`.\n *\n * @static\n * @memberOf _\n * @since 3.9.0\n * @category Lang\n * @param {*} value The value to compare.\n * @param {*} other The other value to compare.\n * @returns {boolean} Returns `true` if `value` is less than `other`,\n * else `false`.\n * @see _.gt\n * @example\n *\n * _.lt(1, 3);\n * // => true\n *\n * _.lt(3, 3);\n * // => false\n *\n * _.lt(3, 1);\n * // => false\n */\n var lt = createRelationalOperation(baseLt);\n\n /**\n * Checks if `value` is less than or equal to `other`.\n *\n * @static\n * @memberOf _\n * @since 3.9.0\n * @category Lang\n * @param {*} value The value to compare.\n * @param {*} other The other value to compare.\n * @returns {boolean} Returns `true` if `value` is less than or equal to\n * `other`, else `false`.\n * @see _.gte\n * @example\n *\n * _.lte(1, 3);\n * // => true\n *\n * _.lte(3, 3);\n * // => true\n *\n * _.lte(3, 1);\n * // => false\n */\n var lte = createRelationalOperation(function(value, other) {\n return value <= other;\n });\n\n /**\n * Converts `value` to an array.\n *\n * @static\n * @since 0.1.0\n * @memberOf _\n * @category Lang\n * @param {*} value The value to convert.\n * @returns {Array} Returns the converted array.\n * @example\n *\n * _.toArray({ 'a': 1, 'b': 2 });\n * // => [1, 2]\n *\n * _.toArray('abc');\n * // => ['a', 'b', 'c']\n *\n * _.toArray(1);\n * // => []\n *\n * _.toArray(null);\n * // => []\n */\n function toArray(value) {\n if (!value) {\n return [];\n }\n if (isArrayLike(value)) {\n return isString(value) ? stringToArray(value) : copyArray(value);\n }\n if (symIterator && value[symIterator]) {\n return iteratorToArray(value[symIterator]());\n }\n var tag = getTag(value),\n func = tag == mapTag ? mapToArray : (tag == setTag ? setToArray : values);\n\n return func(value);\n }\n\n /**\n * Converts `value` to a finite number.\n *\n * @static\n * @memberOf _\n * @since 4.12.0\n * @category Lang\n * @param {*} value The value to convert.\n * @returns {number} Returns the converted number.\n * @example\n *\n * _.toFinite(3.2);\n * // => 3.2\n *\n * _.toFinite(Number.MIN_VALUE);\n * // => 5e-324\n *\n * _.toFinite(Infinity);\n * // => 1.7976931348623157e+308\n *\n * _.toFinite('3.2');\n * // => 3.2\n */\n function toFinite(value) {\n if (!value) {\n return value === 0 ? value : 0;\n }\n value = toNumber(value);\n if (value === INFINITY || value === -INFINITY) {\n var sign = (value < 0 ? -1 : 1);\n return sign * MAX_INTEGER;\n }\n return value === value ? value : 0;\n }\n\n /**\n * Converts `value` to an integer.\n *\n * **Note:** This method is loosely based on\n * [`ToInteger`](http://www.ecma-international.org/ecma-262/7.0/#sec-tointeger).\n *\n * @static\n * @memberOf _\n * @since 4.0.0\n * @category Lang\n * @param {*} value The value to convert.\n * @returns {number} Returns the converted integer.\n * @example\n *\n * _.toInteger(3.2);\n * // => 3\n *\n * _.toInteger(Number.MIN_VALUE);\n * // => 0\n *\n * _.toInteger(Infinity);\n * // => 1.7976931348623157e+308\n *\n * _.toInteger('3.2');\n * // => 3\n */\n function toInteger(value) {\n var result = toFinite(value),\n remainder = result % 1;\n\n return result === result ? (remainder ? result - remainder : result) : 0;\n }\n\n /**\n * Converts `value` to an integer suitable for use as the length of an\n * array-like object.\n *\n * **Note:** This method is based on\n * [`ToLength`](http://ecma-international.org/ecma-262/7.0/#sec-tolength).\n *\n * @static\n * @memberOf _\n * @since 4.0.0\n * @category Lang\n * @param {*} value The value to convert.\n * @returns {number} Returns the converted integer.\n * @example\n *\n * _.toLength(3.2);\n * // => 3\n *\n * _.toLength(Number.MIN_VALUE);\n * // => 0\n *\n * _.toLength(Infinity);\n * // => 4294967295\n *\n * _.toLength('3.2');\n * // => 3\n */\n function toLength(value) {\n return value ? baseClamp(toInteger(value), 0, MAX_ARRAY_LENGTH) : 0;\n }\n\n /**\n * Converts `value` to a number.\n *\n * @static\n * @memberOf _\n * @since 4.0.0\n * @category Lang\n * @param {*} value The value to process.\n * @returns {number} Returns the number.\n * @example\n *\n * _.toNumber(3.2);\n * // => 3.2\n *\n * _.toNumber(Number.MIN_VALUE);\n * // => 5e-324\n *\n * _.toNumber(Infinity);\n * // => Infinity\n *\n * _.toNumber('3.2');\n * // => 3.2\n */\n function toNumber(value) {\n if (typeof value == 'number') {\n return value;\n }\n if (isSymbol(value)) {\n return NAN;\n }\n if (isObject(value)) {\n var other = typeof value.valueOf == 'function' ? value.valueOf() : value;\n value = isObject(other) ? (other + '') : other;\n }\n if (typeof value != 'string') {\n return value === 0 ? value : +value;\n }\n value = baseTrim(value);\n var isBinary = reIsBinary.test(value);\n return (isBinary || reIsOctal.test(value))\n ? freeParseInt(value.slice(2), isBinary ? 2 : 8)\n : (reIsBadHex.test(value) ? NAN : +value);\n }\n\n /**\n * Converts `value` to a plain object flattening inherited enumerable string\n * keyed properties of `value` to own properties of the plain object.\n *\n * @static\n * @memberOf _\n * @since 3.0.0\n * @category Lang\n * @param {*} value The value to convert.\n * @returns {Object} Returns the converted plain object.\n * @example\n *\n * function Foo() {\n * this.b = 2;\n * }\n *\n * Foo.prototype.c = 3;\n *\n * _.assign({ 'a': 1 }, new Foo);\n * // => { 'a': 1, 'b': 2 }\n *\n * _.assign({ 'a': 1 }, _.toPlainObject(new Foo));\n * // => { 'a': 1, 'b': 2, 'c': 3 }\n */\n function toPlainObject(value) {\n return copyObject(value, keysIn(value));\n }\n\n /**\n * Converts `value` to a safe integer. A safe integer can be compared and\n * represented correctly.\n *\n * @static\n * @memberOf _\n * @since 4.0.0\n * @category Lang\n * @param {*} value The value to convert.\n * @returns {number} Returns the converted integer.\n * @example\n *\n * _.toSafeInteger(3.2);\n * // => 3\n *\n * _.toSafeInteger(Number.MIN_VALUE);\n * // => 0\n *\n * _.toSafeInteger(Infinity);\n * // => 9007199254740991\n *\n * _.toSafeInteger('3.2');\n * // => 3\n */\n function toSafeInteger(value) {\n return value\n ? baseClamp(toInteger(value), -MAX_SAFE_INTEGER, MAX_SAFE_INTEGER)\n : (value === 0 ? value : 0);\n }\n\n /**\n * Converts `value` to a string. An empty string is returned for `null`\n * and `undefined` values. The sign of `-0` is preserved.\n *\n * @static\n * @memberOf _\n * @since 4.0.0\n * @category Lang\n * @param {*} value The value to convert.\n * @returns {string} Returns the converted string.\n * @example\n *\n * _.toString(null);\n * // => ''\n *\n * _.toString(-0);\n * // => '-0'\n *\n * _.toString([1, 2, 3]);\n * // => '1,2,3'\n */\n function toString(value) {\n return value == null ? '' : baseToString(value);\n }\n\n /*------------------------------------------------------------------------*/\n\n /**\n * Assigns own enumerable string keyed properties of source objects to the\n * destination object. Source objects are applied from left to right.\n * Subsequent sources overwrite property assignments of previous sources.\n *\n * **Note:** This method mutates `object` and is loosely based on\n * [`Object.assign`](https://mdn.io/Object/assign).\n *\n * @static\n * @memberOf _\n * @since 0.10.0\n * @category Object\n * @param {Object} object The destination object.\n * @param {...Object} [sources] The source objects.\n * @returns {Object} Returns `object`.\n * @see _.assignIn\n * @example\n *\n * function Foo() {\n * this.a = 1;\n * }\n *\n * function Bar() {\n * this.c = 3;\n * }\n *\n * Foo.prototype.b = 2;\n * Bar.prototype.d = 4;\n *\n * _.assign({ 'a': 0 }, new Foo, new Bar);\n * // => { 'a': 1, 'c': 3 }\n */\n var assign = createAssigner(function(object, source) {\n if (isPrototype(source) || isArrayLike(source)) {\n copyObject(source, keys(source), object);\n return;\n }\n for (var key in source) {\n if (hasOwnProperty.call(source, key)) {\n assignValue(object, key, source[key]);\n }\n }\n });\n\n /**\n * This method is like `_.assign` except that it iterates over own and\n * inherited source properties.\n *\n * **Note:** This method mutates `object`.\n *\n * @static\n * @memberOf _\n * @since 4.0.0\n * @alias extend\n * @category Object\n * @param {Object} object The destination object.\n * @param {...Object} [sources] The source objects.\n * @returns {Object} Returns `object`.\n * @see _.assign\n * @example\n *\n * function Foo() {\n * this.a = 1;\n * }\n *\n * function Bar() {\n * this.c = 3;\n * }\n *\n * Foo.prototype.b = 2;\n * Bar.prototype.d = 4;\n *\n * _.assignIn({ 'a': 0 }, new Foo, new Bar);\n * // => { 'a': 1, 'b': 2, 'c': 3, 'd': 4 }\n */\n var assignIn = createAssigner(function(object, source) {\n copyObject(source, keysIn(source), object);\n });\n\n /**\n * This method is like `_.assignIn` except that it accepts `customizer`\n * which is invoked to produce the assigned values. If `customizer` returns\n * `undefined`, assignment is handled by the method instead. The `customizer`\n * is invoked with five arguments: (objValue, srcValue, key, object, source).\n *\n * **Note:** This method mutates `object`.\n *\n * @static\n * @memberOf _\n * @since 4.0.0\n * @alias extendWith\n * @category Object\n * @param {Object} object The destination object.\n * @param {...Object} sources The source objects.\n * @param {Function} [customizer] The function to customize assigned values.\n * @returns {Object} Returns `object`.\n * @see _.assignWith\n * @example\n *\n * function customizer(objValue, srcValue) {\n * return _.isUndefined(objValue) ? srcValue : objValue;\n * }\n *\n * var defaults = _.partialRight(_.assignInWith, customizer);\n *\n * defaults({ 'a': 1 }, { 'b': 2 }, { 'a': 3 });\n * // => { 'a': 1, 'b': 2 }\n */\n var assignInWith = createAssigner(function(object, source, srcIndex, customizer) {\n copyObject(source, keysIn(source), object, customizer);\n });\n\n /**\n * This method is like `_.assign` except that it accepts `customizer`\n * which is invoked to produce the assigned values. If `customizer` returns\n * `undefined`, assignment is handled by the method instead. The `customizer`\n * is invoked with five arguments: (objValue, srcValue, key, object, source).\n *\n * **Note:** This method mutates `object`.\n *\n * @static\n * @memberOf _\n * @since 4.0.0\n * @category Object\n * @param {Object} object The destination object.\n * @param {...Object} sources The source objects.\n * @param {Function} [customizer] The function to customize assigned values.\n * @returns {Object} Returns `object`.\n * @see _.assignInWith\n * @example\n *\n * function customizer(objValue, srcValue) {\n * return _.isUndefined(objValue) ? srcValue : objValue;\n * }\n *\n * var defaults = _.partialRight(_.assignWith, customizer);\n *\n * defaults({ 'a': 1 }, { 'b': 2 }, { 'a': 3 });\n * // => { 'a': 1, 'b': 2 }\n */\n var assignWith = createAssigner(function(object, source, srcIndex, customizer) {\n copyObject(source, keys(source), object, customizer);\n });\n\n /**\n * Creates an array of values corresponding to `paths` of `object`.\n *\n * @static\n * @memberOf _\n * @since 1.0.0\n * @category Object\n * @param {Object} object The object to iterate over.\n * @param {...(string|string[])} [paths] The property paths to pick.\n * @returns {Array} Returns the picked values.\n * @example\n *\n * var object = { 'a': [{ 'b': { 'c': 3 } }, 4] };\n *\n * _.at(object, ['a[0].b.c', 'a[1]']);\n * // => [3, 4]\n */\n var at = flatRest(baseAt);\n\n /**\n * Creates an object that inherits from the `prototype` object. If a\n * `properties` object is given, its own enumerable string keyed properties\n * are assigned to the created object.\n *\n * @static\n * @memberOf _\n * @since 2.3.0\n * @category Object\n * @param {Object} prototype The object to inherit from.\n * @param {Object} [properties] The properties to assign to the object.\n * @returns {Object} Returns the new object.\n * @example\n *\n * function Shape() {\n * this.x = 0;\n * this.y = 0;\n * }\n *\n * function Circle() {\n * Shape.call(this);\n * }\n *\n * Circle.prototype = _.create(Shape.prototype, {\n * 'constructor': Circle\n * });\n *\n * var circle = new Circle;\n * circle instanceof Circle;\n * // => true\n *\n * circle instanceof Shape;\n * // => true\n */\n function create(prototype, properties) {\n var result = baseCreate(prototype);\n return properties == null ? result : baseAssign(result, properties);\n }\n\n /**\n * Assigns own and inherited enumerable string keyed properties of source\n * objects to the destination object for all destination properties that\n * resolve to `undefined`. Source objects are applied from left to right.\n * Once a property is set, additional values of the same property are ignored.\n *\n * **Note:** This method mutates `object`.\n *\n * @static\n * @since 0.1.0\n * @memberOf _\n * @category Object\n * @param {Object} object The destination object.\n * @param {...Object} [sources] The source objects.\n * @returns {Object} Returns `object`.\n * @see _.defaultsDeep\n * @example\n *\n * _.defaults({ 'a': 1 }, { 'b': 2 }, { 'a': 3 });\n * // => { 'a': 1, 'b': 2 }\n */\n var defaults = baseRest(function(object, sources) {\n object = Object(object);\n\n var index = -1;\n var length = sources.length;\n var guard = length > 2 ? sources[2] : undefined;\n\n if (guard && isIterateeCall(sources[0], sources[1], guard)) {\n length = 1;\n }\n\n while (++index < length) {\n var source = sources[index];\n var props = keysIn(source);\n var propsIndex = -1;\n var propsLength = props.length;\n\n while (++propsIndex < propsLength) {\n var key = props[propsIndex];\n var value = object[key];\n\n if (value === undefined ||\n (eq(value, objectProto[key]) && !hasOwnProperty.call(object, key))) {\n object[key] = source[key];\n }\n }\n }\n\n return object;\n });\n\n /**\n * This method is like `_.defaults` except that it recursively assigns\n * default properties.\n *\n * **Note:** This method mutates `object`.\n *\n * @static\n * @memberOf _\n * @since 3.10.0\n * @category Object\n * @param {Object} object The destination object.\n * @param {...Object} [sources] The source objects.\n * @returns {Object} Returns `object`.\n * @see _.defaults\n * @example\n *\n * _.defaultsDeep({ 'a': { 'b': 2 } }, { 'a': { 'b': 1, 'c': 3 } });\n * // => { 'a': { 'b': 2, 'c': 3 } }\n */\n var defaultsDeep = baseRest(function(args) {\n args.push(undefined, customDefaultsMerge);\n return apply(mergeWith, undefined, args);\n });\n\n /**\n * This method is like `_.find` except that it returns the key of the first\n * element `predicate` returns truthy for instead of the element itself.\n *\n * @static\n * @memberOf _\n * @since 1.1.0\n * @category Object\n * @param {Object} object The object to inspect.\n * @param {Function} [predicate=_.identity] The function invoked per iteration.\n * @returns {string|undefined} Returns the key of the matched element,\n * else `undefined`.\n * @example\n *\n * var users = {\n * 'barney': { 'age': 36, 'active': true },\n * 'fred': { 'age': 40, 'active': false },\n * 'pebbles': { 'age': 1, 'active': true }\n * };\n *\n * _.findKey(users, function(o) { return o.age < 40; });\n * // => 'barney' (iteration order is not guaranteed)\n *\n * // The `_.matches` iteratee shorthand.\n * _.findKey(users, { 'age': 1, 'active': true });\n * // => 'pebbles'\n *\n * // The `_.matchesProperty` iteratee shorthand.\n * _.findKey(users, ['active', false]);\n * // => 'fred'\n *\n * // The `_.property` iteratee shorthand.\n * _.findKey(users, 'active');\n * // => 'barney'\n */\n function findKey(object, predicate) {\n return baseFindKey(object, getIteratee(predicate, 3), baseForOwn);\n }\n\n /**\n * This method is like `_.findKey` except that it iterates over elements of\n * a collection in the opposite order.\n *\n * @static\n * @memberOf _\n * @since 2.0.0\n * @category Object\n * @param {Object} object The object to inspect.\n * @param {Function} [predicate=_.identity] The function invoked per iteration.\n * @returns {string|undefined} Returns the key of the matched element,\n * else `undefined`.\n * @example\n *\n * var users = {\n * 'barney': { 'age': 36, 'active': true },\n * 'fred': { 'age': 40, 'active': false },\n * 'pebbles': { 'age': 1, 'active': true }\n * };\n *\n * _.findLastKey(users, function(o) { return o.age < 40; });\n * // => returns 'pebbles' assuming `_.findKey` returns 'barney'\n *\n * // The `_.matches` iteratee shorthand.\n * _.findLastKey(users, { 'age': 36, 'active': true });\n * // => 'barney'\n *\n * // The `_.matchesProperty` iteratee shorthand.\n * _.findLastKey(users, ['active', false]);\n * // => 'fred'\n *\n * // The `_.property` iteratee shorthand.\n * _.findLastKey(users, 'active');\n * // => 'pebbles'\n */\n function findLastKey(object, predicate) {\n return baseFindKey(object, getIteratee(predicate, 3), baseForOwnRight);\n }\n\n /**\n * Iterates over own and inherited enumerable string keyed properties of an\n * object and invokes `iteratee` for each property. The iteratee is invoked\n * with three arguments: (value, key, object). Iteratee functions may exit\n * iteration early by explicitly returning `false`.\n *\n * @static\n * @memberOf _\n * @since 0.3.0\n * @category Object\n * @param {Object} object The object to iterate over.\n * @param {Function} [iteratee=_.identity] The function invoked per iteration.\n * @returns {Object} Returns `object`.\n * @see _.forInRight\n * @example\n *\n * function Foo() {\n * this.a = 1;\n * this.b = 2;\n * }\n *\n * Foo.prototype.c = 3;\n *\n * _.forIn(new Foo, function(value, key) {\n * console.log(key);\n * });\n * // => Logs 'a', 'b', then 'c' (iteration order is not guaranteed).\n */\n function forIn(object, iteratee) {\n return object == null\n ? object\n : baseFor(object, getIteratee(iteratee, 3), keysIn);\n }\n\n /**\n * This method is like `_.forIn` except that it iterates over properties of\n * `object` in the opposite order.\n *\n * @static\n * @memberOf _\n * @since 2.0.0\n * @category Object\n * @param {Object} object The object to iterate over.\n * @param {Function} [iteratee=_.identity] The function invoked per iteration.\n * @returns {Object} Returns `object`.\n * @see _.forIn\n * @example\n *\n * function Foo() {\n * this.a = 1;\n * this.b = 2;\n * }\n *\n * Foo.prototype.c = 3;\n *\n * _.forInRight(new Foo, function(value, key) {\n * console.log(key);\n * });\n * // => Logs 'c', 'b', then 'a' assuming `_.forIn` logs 'a', 'b', then 'c'.\n */\n function forInRight(object, iteratee) {\n return object == null\n ? object\n : baseForRight(object, getIteratee(iteratee, 3), keysIn);\n }\n\n /**\n * Iterates over own enumerable string keyed properties of an object and\n * invokes `iteratee` for each property. The iteratee is invoked with three\n * arguments: (value, key, object). Iteratee functions may exit iteration\n * early by explicitly returning `false`.\n *\n * @static\n * @memberOf _\n * @since 0.3.0\n * @category Object\n * @param {Object} object The object to iterate over.\n * @param {Function} [iteratee=_.identity] The function invoked per iteration.\n * @returns {Object} Returns `object`.\n * @see _.forOwnRight\n * @example\n *\n * function Foo() {\n * this.a = 1;\n * this.b = 2;\n * }\n *\n * Foo.prototype.c = 3;\n *\n * _.forOwn(new Foo, function(value, key) {\n * console.log(key);\n * });\n * // => Logs 'a' then 'b' (iteration order is not guaranteed).\n */\n function forOwn(object, iteratee) {\n return object && baseForOwn(object, getIteratee(iteratee, 3));\n }\n\n /**\n * This method is like `_.forOwn` except that it iterates over properties of\n * `object` in the opposite order.\n *\n * @static\n * @memberOf _\n * @since 2.0.0\n * @category Object\n * @param {Object} object The object to iterate over.\n * @param {Function} [iteratee=_.identity] The function invoked per iteration.\n * @returns {Object} Returns `object`.\n * @see _.forOwn\n * @example\n *\n * function Foo() {\n * this.a = 1;\n * this.b = 2;\n * }\n *\n * Foo.prototype.c = 3;\n *\n * _.forOwnRight(new Foo, function(value, key) {\n * console.log(key);\n * });\n * // => Logs 'b' then 'a' assuming `_.forOwn` logs 'a' then 'b'.\n */\n function forOwnRight(object, iteratee) {\n return object && baseForOwnRight(object, getIteratee(iteratee, 3));\n }\n\n /**\n * Creates an array of function property names from own enumerable properties\n * of `object`.\n *\n * @static\n * @since 0.1.0\n * @memberOf _\n * @category Object\n * @param {Object} object The object to inspect.\n * @returns {Array} Returns the function names.\n * @see _.functionsIn\n * @example\n *\n * function Foo() {\n * this.a = _.constant('a');\n * this.b = _.constant('b');\n * }\n *\n * Foo.prototype.c = _.constant('c');\n *\n * _.functions(new Foo);\n * // => ['a', 'b']\n */\n function functions(object) {\n return object == null ? [] : baseFunctions(object, keys(object));\n }\n\n /**\n * Creates an array of function property names from own and inherited\n * enumerable properties of `object`.\n *\n * @static\n * @memberOf _\n * @since 4.0.0\n * @category Object\n * @param {Object} object The object to inspect.\n * @returns {Array} Returns the function names.\n * @see _.functions\n * @example\n *\n * function Foo() {\n * this.a = _.constant('a');\n * this.b = _.constant('b');\n * }\n *\n * Foo.prototype.c = _.constant('c');\n *\n * _.functionsIn(new Foo);\n * // => ['a', 'b', 'c']\n */\n function functionsIn(object) {\n return object == null ? [] : baseFunctions(object, keysIn(object));\n }\n\n /**\n * Gets the value at `path` of `object`. If the resolved value is\n * `undefined`, the `defaultValue` is returned in its place.\n *\n * @static\n * @memberOf _\n * @since 3.7.0\n * @category Object\n * @param {Object} object The object to query.\n * @param {Array|string} path The path of the property to get.\n * @param {*} [defaultValue] The value returned for `undefined` resolved values.\n * @returns {*} Returns the resolved value.\n * @example\n *\n * var object = { 'a': [{ 'b': { 'c': 3 } }] };\n *\n * _.get(object, 'a[0].b.c');\n * // => 3\n *\n * _.get(object, ['a', '0', 'b', 'c']);\n * // => 3\n *\n * _.get(object, 'a.b.c', 'default');\n * // => 'default'\n */\n function get(object, path, defaultValue) {\n var result = object == null ? undefined : baseGet(object, path);\n return result === undefined ? defaultValue : result;\n }\n\n /**\n * Checks if `path` is a direct property of `object`.\n *\n * @static\n * @since 0.1.0\n * @memberOf _\n * @category Object\n * @param {Object} object The object to query.\n * @param {Array|string} path The path to check.\n * @returns {boolean} Returns `true` if `path` exists, else `false`.\n * @example\n *\n * var object = { 'a': { 'b': 2 } };\n * var other = _.create({ 'a': _.create({ 'b': 2 }) });\n *\n * _.has(object, 'a');\n * // => true\n *\n * _.has(object, 'a.b');\n * // => true\n *\n * _.has(object, ['a', 'b']);\n * // => true\n *\n * _.has(other, 'a');\n * // => false\n */\n function has(object, path) {\n return object != null && hasPath(object, path, baseHas);\n }\n\n /**\n * Checks if `path` is a direct or inherited property of `object`.\n *\n * @static\n * @memberOf _\n * @since 4.0.0\n * @category Object\n * @param {Object} object The object to query.\n * @param {Array|string} path The path to check.\n * @returns {boolean} Returns `true` if `path` exists, else `false`.\n * @example\n *\n * var object = _.create({ 'a': _.create({ 'b': 2 }) });\n *\n * _.hasIn(object, 'a');\n * // => true\n *\n * _.hasIn(object, 'a.b');\n * // => true\n *\n * _.hasIn(object, ['a', 'b']);\n * // => true\n *\n * _.hasIn(object, 'b');\n * // => false\n */\n function hasIn(object, path) {\n return object != null && hasPath(object, path, baseHasIn);\n }\n\n /**\n * Creates an object composed of the inverted keys and values of `object`.\n * If `object` contains duplicate values, subsequent values overwrite\n * property assignments of previous values.\n *\n * @static\n * @memberOf _\n * @since 0.7.0\n * @category Object\n * @param {Object} object The object to invert.\n * @returns {Object} Returns the new inverted object.\n * @example\n *\n * var object = { 'a': 1, 'b': 2, 'c': 1 };\n *\n * _.invert(object);\n * // => { '1': 'c', '2': 'b' }\n */\n var invert = createInverter(function(result, value, key) {\n if (value != null &&\n typeof value.toString != 'function') {\n value = nativeObjectToString.call(value);\n }\n\n result[value] = key;\n }, constant(identity));\n\n /**\n * This method is like `_.invert` except that the inverted object is generated\n * from the results of running each element of `object` thru `iteratee`. The\n * corresponding inverted value of each inverted key is an array of keys\n * responsible for generating the inverted value. The iteratee is invoked\n * with one argument: (value).\n *\n * @static\n * @memberOf _\n * @since 4.1.0\n * @category Object\n * @param {Object} object The object to invert.\n * @param {Function} [iteratee=_.identity] The iteratee invoked per element.\n * @returns {Object} Returns the new inverted object.\n * @example\n *\n * var object = { 'a': 1, 'b': 2, 'c': 1 };\n *\n * _.invertBy(object);\n * // => { '1': ['a', 'c'], '2': ['b'] }\n *\n * _.invertBy(object, function(value) {\n * return 'group' + value;\n * });\n * // => { 'group1': ['a', 'c'], 'group2': ['b'] }\n */\n var invertBy = createInverter(function(result, value, key) {\n if (value != null &&\n typeof value.toString != 'function') {\n value = nativeObjectToString.call(value);\n }\n\n if (hasOwnProperty.call(result, value)) {\n result[value].push(key);\n } else {\n result[value] = [key];\n }\n }, getIteratee);\n\n /**\n * Invokes the method at `path` of `object`.\n *\n * @static\n * @memberOf _\n * @since 4.0.0\n * @category Object\n * @param {Object} object The object to query.\n * @param {Array|string} path The path of the method to invoke.\n * @param {...*} [args] The arguments to invoke the method with.\n * @returns {*} Returns the result of the invoked method.\n * @example\n *\n * var object = { 'a': [{ 'b': { 'c': [1, 2, 3, 4] } }] };\n *\n * _.invoke(object, 'a[0].b.c.slice', 1, 3);\n * // => [2, 3]\n */\n var invoke = baseRest(baseInvoke);\n\n /**\n * Creates an array of the own enumerable property names of `object`.\n *\n * **Note:** Non-object values are coerced to objects. See the\n * [ES spec](http://ecma-international.org/ecma-262/7.0/#sec-object.keys)\n * for more details.\n *\n * @static\n * @since 0.1.0\n * @memberOf _\n * @category Object\n * @param {Object} object The object to query.\n * @returns {Array} Returns the array of property names.\n * @example\n *\n * function Foo() {\n * this.a = 1;\n * this.b = 2;\n * }\n *\n * Foo.prototype.c = 3;\n *\n * _.keys(new Foo);\n * // => ['a', 'b'] (iteration order is not guaranteed)\n *\n * _.keys('hi');\n * // => ['0', '1']\n */\n function keys(object) {\n return isArrayLike(object) ? arrayLikeKeys(object) : baseKeys(object);\n }\n\n /**\n * Creates an array of the own and inherited enumerable property names of `object`.\n *\n * **Note:** Non-object values are coerced to objects.\n *\n * @static\n * @memberOf _\n * @since 3.0.0\n * @category Object\n * @param {Object} object The object to query.\n * @returns {Array} Returns the array of property names.\n * @example\n *\n * function Foo() {\n * this.a = 1;\n * this.b = 2;\n * }\n *\n * Foo.prototype.c = 3;\n *\n * _.keysIn(new Foo);\n * // => ['a', 'b', 'c'] (iteration order is not guaranteed)\n */\n function keysIn(object) {\n return isArrayLike(object) ? arrayLikeKeys(object, true) : baseKeysIn(object);\n }\n\n /**\n * The opposite of `_.mapValues`; this method creates an object with the\n * same values as `object` and keys generated by running each own enumerable\n * string keyed property of `object` thru `iteratee`. The iteratee is invoked\n * with three arguments: (value, key, object).\n *\n * @static\n * @memberOf _\n * @since 3.8.0\n * @category Object\n * @param {Object} object The object to iterate over.\n * @param {Function} [iteratee=_.identity] The function invoked per iteration.\n * @returns {Object} Returns the new mapped object.\n * @see _.mapValues\n * @example\n *\n * _.mapKeys({ 'a': 1, 'b': 2 }, function(value, key) {\n * return key + value;\n * });\n * // => { 'a1': 1, 'b2': 2 }\n */\n function mapKeys(object, iteratee) {\n var result = {};\n iteratee = getIteratee(iteratee, 3);\n\n baseForOwn(object, function(value, key, object) {\n baseAssignValue(result, iteratee(value, key, object), value);\n });\n return result;\n }\n\n /**\n * Creates an object with the same keys as `object` and values generated\n * by running each own enumerable string keyed property of `object` thru\n * `iteratee`. The iteratee is invoked with three arguments:\n * (value, key, object).\n *\n * @static\n * @memberOf _\n * @since 2.4.0\n * @category Object\n * @param {Object} object The object to iterate over.\n * @param {Function} [iteratee=_.identity] The function invoked per iteration.\n * @returns {Object} Returns the new mapped object.\n * @see _.mapKeys\n * @example\n *\n * var users = {\n * 'fred': { 'user': 'fred', 'age': 40 },\n * 'pebbles': { 'user': 'pebbles', 'age': 1 }\n * };\n *\n * _.mapValues(users, function(o) { return o.age; });\n * // => { 'fred': 40, 'pebbles': 1 } (iteration order is not guaranteed)\n *\n * // The `_.property` iteratee shorthand.\n * _.mapValues(users, 'age');\n * // => { 'fred': 40, 'pebbles': 1 } (iteration order is not guaranteed)\n */\n function mapValues(object, iteratee) {\n var result = {};\n iteratee = getIteratee(iteratee, 3);\n\n baseForOwn(object, function(value, key, object) {\n baseAssignValue(result, key, iteratee(value, key, object));\n });\n return result;\n }\n\n /**\n * This method is like `_.assign` except that it recursively merges own and\n * inherited enumerable string keyed properties of source objects into the\n * destination object. Source properties that resolve to `undefined` are\n * skipped if a destination value exists. Array and plain object properties\n * are merged recursively. Other objects and value types are overridden by\n * assignment. Source objects are applied from left to right. Subsequent\n * sources overwrite property assignments of previous sources.\n *\n * **Note:** This method mutates `object`.\n *\n * @static\n * @memberOf _\n * @since 0.5.0\n * @category Object\n * @param {Object} object The destination object.\n * @param {...Object} [sources] The source objects.\n * @returns {Object} Returns `object`.\n * @example\n *\n * var object = {\n * 'a': [{ 'b': 2 }, { 'd': 4 }]\n * };\n *\n * var other = {\n * 'a': [{ 'c': 3 }, { 'e': 5 }]\n * };\n *\n * _.merge(object, other);\n * // => { 'a': [{ 'b': 2, 'c': 3 }, { 'd': 4, 'e': 5 }] }\n */\n var merge = createAssigner(function(object, source, srcIndex) {\n baseMerge(object, source, srcIndex);\n });\n\n /**\n * This method is like `_.merge` except that it accepts `customizer` which\n * is invoked to produce the merged values of the destination and source\n * properties. If `customizer` returns `undefined`, merging is handled by the\n * method instead. The `customizer` is invoked with six arguments:\n * (objValue, srcValue, key, object, source, stack).\n *\n * **Note:** This method mutates `object`.\n *\n * @static\n * @memberOf _\n * @since 4.0.0\n * @category Object\n * @param {Object} object The destination object.\n * @param {...Object} sources The source objects.\n * @param {Function} customizer The function to customize assigned values.\n * @returns {Object} Returns `object`.\n * @example\n *\n * function customizer(objValue, srcValue) {\n * if (_.isArray(objValue)) {\n * return objValue.concat(srcValue);\n * }\n * }\n *\n * var object = { 'a': [1], 'b': [2] };\n * var other = { 'a': [3], 'b': [4] };\n *\n * _.mergeWith(object, other, customizer);\n * // => { 'a': [1, 3], 'b': [2, 4] }\n */\n var mergeWith = createAssigner(function(object, source, srcIndex, customizer) {\n baseMerge(object, source, srcIndex, customizer);\n });\n\n /**\n * The opposite of `_.pick`; this method creates an object composed of the\n * own and inherited enumerable property paths of `object` that are not omitted.\n *\n * **Note:** This method is considerably slower than `_.pick`.\n *\n * @static\n * @since 0.1.0\n * @memberOf _\n * @category Object\n * @param {Object} object The source object.\n * @param {...(string|string[])} [paths] The property paths to omit.\n * @returns {Object} Returns the new object.\n * @example\n *\n * var object = { 'a': 1, 'b': '2', 'c': 3 };\n *\n * _.omit(object, ['a', 'c']);\n * // => { 'b': '2' }\n */\n var omit = flatRest(function(object, paths) {\n var result = {};\n if (object == null) {\n return result;\n }\n var isDeep = false;\n paths = arrayMap(paths, function(path) {\n path = castPath(path, object);\n isDeep || (isDeep = path.length > 1);\n return path;\n });\n copyObject(object, getAllKeysIn(object), result);\n if (isDeep) {\n result = baseClone(result, CLONE_DEEP_FLAG | CLONE_FLAT_FLAG | CLONE_SYMBOLS_FLAG, customOmitClone);\n }\n var length = paths.length;\n while (length--) {\n baseUnset(result, paths[length]);\n }\n return result;\n });\n\n /**\n * The opposite of `_.pickBy`; this method creates an object composed of\n * the own and inherited enumerable string keyed properties of `object` that\n * `predicate` doesn't return truthy for. The predicate is invoked with two\n * arguments: (value, key).\n *\n * @static\n * @memberOf _\n * @since 4.0.0\n * @category Object\n * @param {Object} object The source object.\n * @param {Function} [predicate=_.identity] The function invoked per property.\n * @returns {Object} Returns the new object.\n * @example\n *\n * var object = { 'a': 1, 'b': '2', 'c': 3 };\n *\n * _.omitBy(object, _.isNumber);\n * // => { 'b': '2' }\n */\n function omitBy(object, predicate) {\n return pickBy(object, negate(getIteratee(predicate)));\n }\n\n /**\n * Creates an object composed of the picked `object` properties.\n *\n * @static\n * @since 0.1.0\n * @memberOf _\n * @category Object\n * @param {Object} object The source object.\n * @param {...(string|string[])} [paths] The property paths to pick.\n * @returns {Object} Returns the new object.\n * @example\n *\n * var object = { 'a': 1, 'b': '2', 'c': 3 };\n *\n * _.pick(object, ['a', 'c']);\n * // => { 'a': 1, 'c': 3 }\n */\n var pick = flatRest(function(object, paths) {\n return object == null ? {} : basePick(object, paths);\n });\n\n /**\n * Creates an object composed of the `object` properties `predicate` returns\n * truthy for. The predicate is invoked with two arguments: (value, key).\n *\n * @static\n * @memberOf _\n * @since 4.0.0\n * @category Object\n * @param {Object} object The source object.\n * @param {Function} [predicate=_.identity] The function invoked per property.\n * @returns {Object} Returns the new object.\n * @example\n *\n * var object = { 'a': 1, 'b': '2', 'c': 3 };\n *\n * _.pickBy(object, _.isNumber);\n * // => { 'a': 1, 'c': 3 }\n */\n function pickBy(object, predicate) {\n if (object == null) {\n return {};\n }\n var props = arrayMap(getAllKeysIn(object), function(prop) {\n return [prop];\n });\n predicate = getIteratee(predicate);\n return basePickBy(object, props, function(value, path) {\n return predicate(value, path[0]);\n });\n }\n\n /**\n * This method is like `_.get` except that if the resolved value is a\n * function it's invoked with the `this` binding of its parent object and\n * its result is returned.\n *\n * @static\n * @since 0.1.0\n * @memberOf _\n * @category Object\n * @param {Object} object The object to query.\n * @param {Array|string} path The path of the property to resolve.\n * @param {*} [defaultValue] The value returned for `undefined` resolved values.\n * @returns {*} Returns the resolved value.\n * @example\n *\n * var object = { 'a': [{ 'b': { 'c1': 3, 'c2': _.constant(4) } }] };\n *\n * _.result(object, 'a[0].b.c1');\n * // => 3\n *\n * _.result(object, 'a[0].b.c2');\n * // => 4\n *\n * _.result(object, 'a[0].b.c3', 'default');\n * // => 'default'\n *\n * _.result(object, 'a[0].b.c3', _.constant('default'));\n * // => 'default'\n */\n function result(object, path, defaultValue) {\n path = castPath(path, object);\n\n var index = -1,\n length = path.length;\n\n // Ensure the loop is entered when path is empty.\n if (!length) {\n length = 1;\n object = undefined;\n }\n while (++index < length) {\n var value = object == null ? undefined : object[toKey(path[index])];\n if (value === undefined) {\n index = length;\n value = defaultValue;\n }\n object = isFunction(value) ? value.call(object) : value;\n }\n return object;\n }\n\n /**\n * Sets the value at `path` of `object`. If a portion of `path` doesn't exist,\n * it's created. Arrays are created for missing index properties while objects\n * are created for all other missing properties. Use `_.setWith` to customize\n * `path` creation.\n *\n * **Note:** This method mutates `object`.\n *\n * @static\n * @memberOf _\n * @since 3.7.0\n * @category Object\n * @param {Object} object The object to modify.\n * @param {Array|string} path The path of the property to set.\n * @param {*} value The value to set.\n * @returns {Object} Returns `object`.\n * @example\n *\n * var object = { 'a': [{ 'b': { 'c': 3 } }] };\n *\n * _.set(object, 'a[0].b.c', 4);\n * console.log(object.a[0].b.c);\n * // => 4\n *\n * _.set(object, ['x', '0', 'y', 'z'], 5);\n * console.log(object.x[0].y.z);\n * // => 5\n */\n function set(object, path, value) {\n return object == null ? object : baseSet(object, path, value);\n }\n\n /**\n * This method is like `_.set` except that it accepts `customizer` which is\n * invoked to produce the objects of `path`. If `customizer` returns `undefined`\n * path creation is handled by the method instead. The `customizer` is invoked\n * with three arguments: (nsValue, key, nsObject).\n *\n * **Note:** This method mutates `object`.\n *\n * @static\n * @memberOf _\n * @since 4.0.0\n * @category Object\n * @param {Object} object The object to modify.\n * @param {Array|string} path The path of the property to set.\n * @param {*} value The value to set.\n * @param {Function} [customizer] The function to customize assigned values.\n * @returns {Object} Returns `object`.\n * @example\n *\n * var object = {};\n *\n * _.setWith(object, '[0][1]', 'a', Object);\n * // => { '0': { '1': 'a' } }\n */\n function setWith(object, path, value, customizer) {\n customizer = typeof customizer == 'function' ? customizer : undefined;\n return object == null ? object : baseSet(object, path, value, customizer);\n }\n\n /**\n * Creates an array of own enumerable string keyed-value pairs for `object`\n * which can be consumed by `_.fromPairs`. If `object` is a map or set, its\n * entries are returned.\n *\n * @static\n * @memberOf _\n * @since 4.0.0\n * @alias entries\n * @category Object\n * @param {Object} object The object to query.\n * @returns {Array} Returns the key-value pairs.\n * @example\n *\n * function Foo() {\n * this.a = 1;\n * this.b = 2;\n * }\n *\n * Foo.prototype.c = 3;\n *\n * _.toPairs(new Foo);\n * // => [['a', 1], ['b', 2]] (iteration order is not guaranteed)\n */\n var toPairs = createToPairs(keys);\n\n /**\n * Creates an array of own and inherited enumerable string keyed-value pairs\n * for `object` which can be consumed by `_.fromPairs`. If `object` is a map\n * or set, its entries are returned.\n *\n * @static\n * @memberOf _\n * @since 4.0.0\n * @alias entriesIn\n * @category Object\n * @param {Object} object The object to query.\n * @returns {Array} Returns the key-value pairs.\n * @example\n *\n * function Foo() {\n * this.a = 1;\n * this.b = 2;\n * }\n *\n * Foo.prototype.c = 3;\n *\n * _.toPairsIn(new Foo);\n * // => [['a', 1], ['b', 2], ['c', 3]] (iteration order is not guaranteed)\n */\n var toPairsIn = createToPairs(keysIn);\n\n /**\n * An alternative to `_.reduce`; this method transforms `object` to a new\n * `accumulator` object which is the result of running each of its own\n * enumerable string keyed properties thru `iteratee`, with each invocation\n * potentially mutating the `accumulator` object. If `accumulator` is not\n * provided, a new object with the same `[[Prototype]]` will be used. The\n * iteratee is invoked with four arguments: (accumulator, value, key, object).\n * Iteratee functions may exit iteration early by explicitly returning `false`.\n *\n * @static\n * @memberOf _\n * @since 1.3.0\n * @category Object\n * @param {Object} object The object to iterate over.\n * @param {Function} [iteratee=_.identity] The function invoked per iteration.\n * @param {*} [accumulator] The custom accumulator value.\n * @returns {*} Returns the accumulated value.\n * @example\n *\n * _.transform([2, 3, 4], function(result, n) {\n * result.push(n *= n);\n * return n % 2 == 0;\n * }, []);\n * // => [4, 9]\n *\n * _.transform({ 'a': 1, 'b': 2, 'c': 1 }, function(result, value, key) {\n * (result[value] || (result[value] = [])).push(key);\n * }, {});\n * // => { '1': ['a', 'c'], '2': ['b'] }\n */\n function transform(object, iteratee, accumulator) {\n var isArr = isArray(object),\n isArrLike = isArr || isBuffer(object) || isTypedArray(object);\n\n iteratee = getIteratee(iteratee, 4);\n if (accumulator == null) {\n var Ctor = object && object.constructor;\n if (isArrLike) {\n accumulator = isArr ? new Ctor : [];\n }\n else if (isObject(object)) {\n accumulator = isFunction(Ctor) ? baseCreate(getPrototype(object)) : {};\n }\n else {\n accumulator = {};\n }\n }\n (isArrLike ? arrayEach : baseForOwn)(object, function(value, index, object) {\n return iteratee(accumulator, value, index, object);\n });\n return accumulator;\n }\n\n /**\n * Removes the property at `path` of `object`.\n *\n * **Note:** This method mutates `object`.\n *\n * @static\n * @memberOf _\n * @since 4.0.0\n * @category Object\n * @param {Object} object The object to modify.\n * @param {Array|string} path The path of the property to unset.\n * @returns {boolean} Returns `true` if the property is deleted, else `false`.\n * @example\n *\n * var object = { 'a': [{ 'b': { 'c': 7 } }] };\n * _.unset(object, 'a[0].b.c');\n * // => true\n *\n * console.log(object);\n * // => { 'a': [{ 'b': {} }] };\n *\n * _.unset(object, ['a', '0', 'b', 'c']);\n * // => true\n *\n * console.log(object);\n * // => { 'a': [{ 'b': {} }] };\n */\n function unset(object, path) {\n return object == null ? true : baseUnset(object, path);\n }\n\n /**\n * This method is like `_.set` except that accepts `updater` to produce the\n * value to set. Use `_.updateWith` to customize `path` creation. The `updater`\n * is invoked with one argument: (value).\n *\n * **Note:** This method mutates `object`.\n *\n * @static\n * @memberOf _\n * @since 4.6.0\n * @category Object\n * @param {Object} object The object to modify.\n * @param {Array|string} path The path of the property to set.\n * @param {Function} updater The function to produce the updated value.\n * @returns {Object} Returns `object`.\n * @example\n *\n * var object = { 'a': [{ 'b': { 'c': 3 } }] };\n *\n * _.update(object, 'a[0].b.c', function(n) { return n * n; });\n * console.log(object.a[0].b.c);\n * // => 9\n *\n * _.update(object, 'x[0].y.z', function(n) { return n ? n + 1 : 0; });\n * console.log(object.x[0].y.z);\n * // => 0\n */\n function update(object, path, updater) {\n return object == null ? object : baseUpdate(object, path, castFunction(updater));\n }\n\n /**\n * This method is like `_.update` except that it accepts `customizer` which is\n * invoked to produce the objects of `path`. If `customizer` returns `undefined`\n * path creation is handled by the method instead. The `customizer` is invoked\n * with three arguments: (nsValue, key, nsObject).\n *\n * **Note:** This method mutates `object`.\n *\n * @static\n * @memberOf _\n * @since 4.6.0\n * @category Object\n * @param {Object} object The object to modify.\n * @param {Array|string} path The path of the property to set.\n * @param {Function} updater The function to produce the updated value.\n * @param {Function} [customizer] The function to customize assigned values.\n * @returns {Object} Returns `object`.\n * @example\n *\n * var object = {};\n *\n * _.updateWith(object, '[0][1]', _.constant('a'), Object);\n * // => { '0': { '1': 'a' } }\n */\n function updateWith(object, path, updater, customizer) {\n customizer = typeof customizer == 'function' ? customizer : undefined;\n return object == null ? object : baseUpdate(object, path, castFunction(updater), customizer);\n }\n\n /**\n * Creates an array of the own enumerable string keyed property values of `object`.\n *\n * **Note:** Non-object values are coerced to objects.\n *\n * @static\n * @since 0.1.0\n * @memberOf _\n * @category Object\n * @param {Object} object The object to query.\n * @returns {Array} Returns the array of property values.\n * @example\n *\n * function Foo() {\n * this.a = 1;\n * this.b = 2;\n * }\n *\n * Foo.prototype.c = 3;\n *\n * _.values(new Foo);\n * // => [1, 2] (iteration order is not guaranteed)\n *\n * _.values('hi');\n * // => ['h', 'i']\n */\n function values(object) {\n return object == null ? [] : baseValues(object, keys(object));\n }\n\n /**\n * Creates an array of the own and inherited enumerable string keyed property\n * values of `object`.\n *\n * **Note:** Non-object values are coerced to objects.\n *\n * @static\n * @memberOf _\n * @since 3.0.0\n * @category Object\n * @param {Object} object The object to query.\n * @returns {Array} Returns the array of property values.\n * @example\n *\n * function Foo() {\n * this.a = 1;\n * this.b = 2;\n * }\n *\n * Foo.prototype.c = 3;\n *\n * _.valuesIn(new Foo);\n * // => [1, 2, 3] (iteration order is not guaranteed)\n */\n function valuesIn(object) {\n return object == null ? [] : baseValues(object, keysIn(object));\n }\n\n /*------------------------------------------------------------------------*/\n\n /**\n * Clamps `number` within the inclusive `lower` and `upper` bounds.\n *\n * @static\n * @memberOf _\n * @since 4.0.0\n * @category Number\n * @param {number} number The number to clamp.\n * @param {number} [lower] The lower bound.\n * @param {number} upper The upper bound.\n * @returns {number} Returns the clamped number.\n * @example\n *\n * _.clamp(-10, -5, 5);\n * // => -5\n *\n * _.clamp(10, -5, 5);\n * // => 5\n */\n function clamp(number, lower, upper) {\n if (upper === undefined) {\n upper = lower;\n lower = undefined;\n }\n if (upper !== undefined) {\n upper = toNumber(upper);\n upper = upper === upper ? upper : 0;\n }\n if (lower !== undefined) {\n lower = toNumber(lower);\n lower = lower === lower ? lower : 0;\n }\n return baseClamp(toNumber(number), lower, upper);\n }\n\n /**\n * Checks if `n` is between `start` and up to, but not including, `end`. If\n * `end` is not specified, it's set to `start` with `start` then set to `0`.\n * If `start` is greater than `end` the params are swapped to support\n * negative ranges.\n *\n * @static\n * @memberOf _\n * @since 3.3.0\n * @category Number\n * @param {number} number The number to check.\n * @param {number} [start=0] The start of the range.\n * @param {number} end The end of the range.\n * @returns {boolean} Returns `true` if `number` is in the range, else `false`.\n * @see _.range, _.rangeRight\n * @example\n *\n * _.inRange(3, 2, 4);\n * // => true\n *\n * _.inRange(4, 8);\n * // => true\n *\n * _.inRange(4, 2);\n * // => false\n *\n * _.inRange(2, 2);\n * // => false\n *\n * _.inRange(1.2, 2);\n * // => true\n *\n * _.inRange(5.2, 4);\n * // => false\n *\n * _.inRange(-3, -2, -6);\n * // => true\n */\n function inRange(number, start, end) {\n start = toFinite(start);\n if (end === undefined) {\n end = start;\n start = 0;\n } else {\n end = toFinite(end);\n }\n number = toNumber(number);\n return baseInRange(number, start, end);\n }\n\n /**\n * Produces a random number between the inclusive `lower` and `upper` bounds.\n * If only one argument is provided a number between `0` and the given number\n * is returned. If `floating` is `true`, or either `lower` or `upper` are\n * floats, a floating-point number is returned instead of an integer.\n *\n * **Note:** JavaScript follows the IEEE-754 standard for resolving\n * floating-point values which can produce unexpected results.\n *\n * @static\n * @memberOf _\n * @since 0.7.0\n * @category Number\n * @param {number} [lower=0] The lower bound.\n * @param {number} [upper=1] The upper bound.\n * @param {boolean} [floating] Specify returning a floating-point number.\n * @returns {number} Returns the random number.\n * @example\n *\n * _.random(0, 5);\n * // => an integer between 0 and 5\n *\n * _.random(5);\n * // => also an integer between 0 and 5\n *\n * _.random(5, true);\n * // => a floating-point number between 0 and 5\n *\n * _.random(1.2, 5.2);\n * // => a floating-point number between 1.2 and 5.2\n */\n function random(lower, upper, floating) {\n if (floating && typeof floating != 'boolean' && isIterateeCall(lower, upper, floating)) {\n upper = floating = undefined;\n }\n if (floating === undefined) {\n if (typeof upper == 'boolean') {\n floating = upper;\n upper = undefined;\n }\n else if (typeof lower == 'boolean') {\n floating = lower;\n lower = undefined;\n }\n }\n if (lower === undefined && upper === undefined) {\n lower = 0;\n upper = 1;\n }\n else {\n lower = toFinite(lower);\n if (upper === undefined) {\n upper = lower;\n lower = 0;\n } else {\n upper = toFinite(upper);\n }\n }\n if (lower > upper) {\n var temp = lower;\n lower = upper;\n upper = temp;\n }\n if (floating || lower % 1 || upper % 1) {\n var rand = nativeRandom();\n return nativeMin(lower + (rand * (upper - lower + freeParseFloat('1e-' + ((rand + '').length - 1)))), upper);\n }\n return baseRandom(lower, upper);\n }\n\n /*------------------------------------------------------------------------*/\n\n /**\n * Converts `string` to [camel case](https://en.wikipedia.org/wiki/CamelCase).\n *\n * @static\n * @memberOf _\n * @since 3.0.0\n * @category String\n * @param {string} [string=''] The string to convert.\n * @returns {string} Returns the camel cased string.\n * @example\n *\n * _.camelCase('Foo Bar');\n * // => 'fooBar'\n *\n * _.camelCase('--foo-bar--');\n * // => 'fooBar'\n *\n * _.camelCase('__FOO_BAR__');\n * // => 'fooBar'\n */\n var camelCase = createCompounder(function(result, word, index) {\n word = word.toLowerCase();\n return result + (index ? capitalize(word) : word);\n });\n\n /**\n * Converts the first character of `string` to upper case and the remaining\n * to lower case.\n *\n * @static\n * @memberOf _\n * @since 3.0.0\n * @category String\n * @param {string} [string=''] The string to capitalize.\n * @returns {string} Returns the capitalized string.\n * @example\n *\n * _.capitalize('FRED');\n * // => 'Fred'\n */\n function capitalize(string) {\n return upperFirst(toString(string).toLowerCase());\n }\n\n /**\n * Deburrs `string` by converting\n * [Latin-1 Supplement](https://en.wikipedia.org/wiki/Latin-1_Supplement_(Unicode_block)#Character_table)\n * and [Latin Extended-A](https://en.wikipedia.org/wiki/Latin_Extended-A)\n * letters to basic Latin letters and removing\n * [combining diacritical marks](https://en.wikipedia.org/wiki/Combining_Diacritical_Marks).\n *\n * @static\n * @memberOf _\n * @since 3.0.0\n * @category String\n * @param {string} [string=''] The string to deburr.\n * @returns {string} Returns the deburred string.\n * @example\n *\n * _.deburr('déjà vu');\n * // => 'deja vu'\n */\n function deburr(string) {\n string = toString(string);\n return string && string.replace(reLatin, deburrLetter).replace(reComboMark, '');\n }\n\n /**\n * Checks if `string` ends with the given target string.\n *\n * @static\n * @memberOf _\n * @since 3.0.0\n * @category String\n * @param {string} [string=''] The string to inspect.\n * @param {string} [target] The string to search for.\n * @param {number} [position=string.length] The position to search up to.\n * @returns {boolean} Returns `true` if `string` ends with `target`,\n * else `false`.\n * @example\n *\n * _.endsWith('abc', 'c');\n * // => true\n *\n * _.endsWith('abc', 'b');\n * // => false\n *\n * _.endsWith('abc', 'b', 2);\n * // => true\n */\n function endsWith(string, target, position) {\n string = toString(string);\n target = baseToString(target);\n\n var length = string.length;\n position = position === undefined\n ? length\n : baseClamp(toInteger(position), 0, length);\n\n var end = position;\n position -= target.length;\n return position >= 0 && string.slice(position, end) == target;\n }\n\n /**\n * Converts the characters \"&\", \"<\", \">\", '\"', and \"'\" in `string` to their\n * corresponding HTML entities.\n *\n * **Note:** No other characters are escaped. To escape additional\n * characters use a third-party library like [_he_](https://mths.be/he).\n *\n * Though the \">\" character is escaped for symmetry, characters like\n * \">\" and \"/\" don't need escaping in HTML and have no special meaning\n * unless they're part of a tag or unquoted attribute value. See\n * [Mathias Bynens's article](https://mathiasbynens.be/notes/ambiguous-ampersands)\n * (under \"semi-related fun fact\") for more details.\n *\n * When working with HTML you should always\n * [quote attribute values](http://wonko.com/post/html-escaping) to reduce\n * XSS vectors.\n *\n * @static\n * @since 0.1.0\n * @memberOf _\n * @category String\n * @param {string} [string=''] The string to escape.\n * @returns {string} Returns the escaped string.\n * @example\n *\n * _.escape('fred, barney, & pebbles');\n * // => 'fred, barney, & pebbles'\n */\n function escape(string) {\n string = toString(string);\n return (string && reHasUnescapedHtml.test(string))\n ? string.replace(reUnescapedHtml, escapeHtmlChar)\n : string;\n }\n\n /**\n * Escapes the `RegExp` special characters \"^\", \"$\", \"\\\", \".\", \"*\", \"+\",\n * \"?\", \"(\", \")\", \"[\", \"]\", \"{\", \"}\", and \"|\" in `string`.\n *\n * @static\n * @memberOf _\n * @since 3.0.0\n * @category String\n * @param {string} [string=''] The string to escape.\n * @returns {string} Returns the escaped string.\n * @example\n *\n * _.escapeRegExp('[lodash](https://lodash.com/)');\n * // => '\\[lodash\\]\\(https://lodash\\.com/\\)'\n */\n function escapeRegExp(string) {\n string = toString(string);\n return (string && reHasRegExpChar.test(string))\n ? string.replace(reRegExpChar, '\\\\$&')\n : string;\n }\n\n /**\n * Converts `string` to\n * [kebab case](https://en.wikipedia.org/wiki/Letter_case#Special_case_styles).\n *\n * @static\n * @memberOf _\n * @since 3.0.0\n * @category String\n * @param {string} [string=''] The string to convert.\n * @returns {string} Returns the kebab cased string.\n * @example\n *\n * _.kebabCase('Foo Bar');\n * // => 'foo-bar'\n *\n * _.kebabCase('fooBar');\n * // => 'foo-bar'\n *\n * _.kebabCase('__FOO_BAR__');\n * // => 'foo-bar'\n */\n var kebabCase = createCompounder(function(result, word, index) {\n return result + (index ? '-' : '') + word.toLowerCase();\n });\n\n /**\n * Converts `string`, as space separated words, to lower case.\n *\n * @static\n * @memberOf _\n * @since 4.0.0\n * @category String\n * @param {string} [string=''] The string to convert.\n * @returns {string} Returns the lower cased string.\n * @example\n *\n * _.lowerCase('--Foo-Bar--');\n * // => 'foo bar'\n *\n * _.lowerCase('fooBar');\n * // => 'foo bar'\n *\n * _.lowerCase('__FOO_BAR__');\n * // => 'foo bar'\n */\n var lowerCase = createCompounder(function(result, word, index) {\n return result + (index ? ' ' : '') + word.toLowerCase();\n });\n\n /**\n * Converts the first character of `string` to lower case.\n *\n * @static\n * @memberOf _\n * @since 4.0.0\n * @category String\n * @param {string} [string=''] The string to convert.\n * @returns {string} Returns the converted string.\n * @example\n *\n * _.lowerFirst('Fred');\n * // => 'fred'\n *\n * _.lowerFirst('FRED');\n * // => 'fRED'\n */\n var lowerFirst = createCaseFirst('toLowerCase');\n\n /**\n * Pads `string` on the left and right sides if it's shorter than `length`.\n * Padding characters are truncated if they can't be evenly divided by `length`.\n *\n * @static\n * @memberOf _\n * @since 3.0.0\n * @category String\n * @param {string} [string=''] The string to pad.\n * @param {number} [length=0] The padding length.\n * @param {string} [chars=' '] The string used as padding.\n * @returns {string} Returns the padded string.\n * @example\n *\n * _.pad('abc', 8);\n * // => ' abc '\n *\n * _.pad('abc', 8, '_-');\n * // => '_-abc_-_'\n *\n * _.pad('abc', 3);\n * // => 'abc'\n */\n function pad(string, length, chars) {\n string = toString(string);\n length = toInteger(length);\n\n var strLength = length ? stringSize(string) : 0;\n if (!length || strLength >= length) {\n return string;\n }\n var mid = (length - strLength) / 2;\n return (\n createPadding(nativeFloor(mid), chars) +\n string +\n createPadding(nativeCeil(mid), chars)\n );\n }\n\n /**\n * Pads `string` on the right side if it's shorter than `length`. Padding\n * characters are truncated if they exceed `length`.\n *\n * @static\n * @memberOf _\n * @since 4.0.0\n * @category String\n * @param {string} [string=''] The string to pad.\n * @param {number} [length=0] The padding length.\n * @param {string} [chars=' '] The string used as padding.\n * @returns {string} Returns the padded string.\n * @example\n *\n * _.padEnd('abc', 6);\n * // => 'abc '\n *\n * _.padEnd('abc', 6, '_-');\n * // => 'abc_-_'\n *\n * _.padEnd('abc', 3);\n * // => 'abc'\n */\n function padEnd(string, length, chars) {\n string = toString(string);\n length = toInteger(length);\n\n var strLength = length ? stringSize(string) : 0;\n return (length && strLength < length)\n ? (string + createPadding(length - strLength, chars))\n : string;\n }\n\n /**\n * Pads `string` on the left side if it's shorter than `length`. Padding\n * characters are truncated if they exceed `length`.\n *\n * @static\n * @memberOf _\n * @since 4.0.0\n * @category String\n * @param {string} [string=''] The string to pad.\n * @param {number} [length=0] The padding length.\n * @param {string} [chars=' '] The string used as padding.\n * @returns {string} Returns the padded string.\n * @example\n *\n * _.padStart('abc', 6);\n * // => ' abc'\n *\n * _.padStart('abc', 6, '_-');\n * // => '_-_abc'\n *\n * _.padStart('abc', 3);\n * // => 'abc'\n */\n function padStart(string, length, chars) {\n string = toString(string);\n length = toInteger(length);\n\n var strLength = length ? stringSize(string) : 0;\n return (length && strLength < length)\n ? (createPadding(length - strLength, chars) + string)\n : string;\n }\n\n /**\n * Converts `string` to an integer of the specified radix. If `radix` is\n * `undefined` or `0`, a `radix` of `10` is used unless `value` is a\n * hexadecimal, in which case a `radix` of `16` is used.\n *\n * **Note:** This method aligns with the\n * [ES5 implementation](https://es5.github.io/#x15.1.2.2) of `parseInt`.\n *\n * @static\n * @memberOf _\n * @since 1.1.0\n * @category String\n * @param {string} string The string to convert.\n * @param {number} [radix=10] The radix to interpret `value` by.\n * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.\n * @returns {number} Returns the converted integer.\n * @example\n *\n * _.parseInt('08');\n * // => 8\n *\n * _.map(['6', '08', '10'], _.parseInt);\n * // => [6, 8, 10]\n */\n function parseInt(string, radix, guard) {\n if (guard || radix == null) {\n radix = 0;\n } else if (radix) {\n radix = +radix;\n }\n return nativeParseInt(toString(string).replace(reTrimStart, ''), radix || 0);\n }\n\n /**\n * Repeats the given string `n` times.\n *\n * @static\n * @memberOf _\n * @since 3.0.0\n * @category String\n * @param {string} [string=''] The string to repeat.\n * @param {number} [n=1] The number of times to repeat the string.\n * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.\n * @returns {string} Returns the repeated string.\n * @example\n *\n * _.repeat('*', 3);\n * // => '***'\n *\n * _.repeat('abc', 2);\n * // => 'abcabc'\n *\n * _.repeat('abc', 0);\n * // => ''\n */\n function repeat(string, n, guard) {\n if ((guard ? isIterateeCall(string, n, guard) : n === undefined)) {\n n = 1;\n } else {\n n = toInteger(n);\n }\n return baseRepeat(toString(string), n);\n }\n\n /**\n * Replaces matches for `pattern` in `string` with `replacement`.\n *\n * **Note:** This method is based on\n * [`String#replace`](https://mdn.io/String/replace).\n *\n * @static\n * @memberOf _\n * @since 4.0.0\n * @category String\n * @param {string} [string=''] The string to modify.\n * @param {RegExp|string} pattern The pattern to replace.\n * @param {Function|string} replacement The match replacement.\n * @returns {string} Returns the modified string.\n * @example\n *\n * _.replace('Hi Fred', 'Fred', 'Barney');\n * // => 'Hi Barney'\n */\n function replace() {\n var args = arguments,\n string = toString(args[0]);\n\n return args.length < 3 ? string : string.replace(args[1], args[2]);\n }\n\n /**\n * Converts `string` to\n * [snake case](https://en.wikipedia.org/wiki/Snake_case).\n *\n * @static\n * @memberOf _\n * @since 3.0.0\n * @category String\n * @param {string} [string=''] The string to convert.\n * @returns {string} Returns the snake cased string.\n * @example\n *\n * _.snakeCase('Foo Bar');\n * // => 'foo_bar'\n *\n * _.snakeCase('fooBar');\n * // => 'foo_bar'\n *\n * _.snakeCase('--FOO-BAR--');\n * // => 'foo_bar'\n */\n var snakeCase = createCompounder(function(result, word, index) {\n return result + (index ? '_' : '') + word.toLowerCase();\n });\n\n /**\n * Splits `string` by `separator`.\n *\n * **Note:** This method is based on\n * [`String#split`](https://mdn.io/String/split).\n *\n * @static\n * @memberOf _\n * @since 4.0.0\n * @category String\n * @param {string} [string=''] The string to split.\n * @param {RegExp|string} separator The separator pattern to split by.\n * @param {number} [limit] The length to truncate results to.\n * @returns {Array} Returns the string segments.\n * @example\n *\n * _.split('a-b-c', '-', 2);\n * // => ['a', 'b']\n */\n function split(string, separator, limit) {\n if (limit && typeof limit != 'number' && isIterateeCall(string, separator, limit)) {\n separator = limit = undefined;\n }\n limit = limit === undefined ? MAX_ARRAY_LENGTH : limit >>> 0;\n if (!limit) {\n return [];\n }\n string = toString(string);\n if (string && (\n typeof separator == 'string' ||\n (separator != null && !isRegExp(separator))\n )) {\n separator = baseToString(separator);\n if (!separator && hasUnicode(string)) {\n return castSlice(stringToArray(string), 0, limit);\n }\n }\n return string.split(separator, limit);\n }\n\n /**\n * Converts `string` to\n * [start case](https://en.wikipedia.org/wiki/Letter_case#Stylistic_or_specialised_usage).\n *\n * @static\n * @memberOf _\n * @since 3.1.0\n * @category String\n * @param {string} [string=''] The string to convert.\n * @returns {string} Returns the start cased string.\n * @example\n *\n * _.startCase('--foo-bar--');\n * // => 'Foo Bar'\n *\n * _.startCase('fooBar');\n * // => 'Foo Bar'\n *\n * _.startCase('__FOO_BAR__');\n * // => 'FOO BAR'\n */\n var startCase = createCompounder(function(result, word, index) {\n return result + (index ? ' ' : '') + upperFirst(word);\n });\n\n /**\n * Checks if `string` starts with the given target string.\n *\n * @static\n * @memberOf _\n * @since 3.0.0\n * @category String\n * @param {string} [string=''] The string to inspect.\n * @param {string} [target] The string to search for.\n * @param {number} [position=0] The position to search from.\n * @returns {boolean} Returns `true` if `string` starts with `target`,\n * else `false`.\n * @example\n *\n * _.startsWith('abc', 'a');\n * // => true\n *\n * _.startsWith('abc', 'b');\n * // => false\n *\n * _.startsWith('abc', 'b', 1);\n * // => true\n */\n function startsWith(string, target, position) {\n string = toString(string);\n position = position == null\n ? 0\n : baseClamp(toInteger(position), 0, string.length);\n\n target = baseToString(target);\n return string.slice(position, position + target.length) == target;\n }\n\n /**\n * Creates a compiled template function that can interpolate data properties\n * in \"interpolate\" delimiters, HTML-escape interpolated data properties in\n * \"escape\" delimiters, and execute JavaScript in \"evaluate\" delimiters. Data\n * properties may be accessed as free variables in the template. If a setting\n * object is given, it takes precedence over `_.templateSettings` values.\n *\n * **Note:** In the development build `_.template` utilizes\n * [sourceURLs](http://www.html5rocks.com/en/tutorials/developertools/sourcemaps/#toc-sourceurl)\n * for easier debugging.\n *\n * For more information on precompiling templates see\n * [lodash's custom builds documentation](https://lodash.com/custom-builds).\n *\n * For more information on Chrome extension sandboxes see\n * [Chrome's extensions documentation](https://developer.chrome.com/extensions/sandboxingEval).\n *\n * @static\n * @since 0.1.0\n * @memberOf _\n * @category String\n * @param {string} [string=''] The template string.\n * @param {Object} [options={}] The options object.\n * @param {RegExp} [options.escape=_.templateSettings.escape]\n * The HTML \"escape\" delimiter.\n * @param {RegExp} [options.evaluate=_.templateSettings.evaluate]\n * The \"evaluate\" delimiter.\n * @param {Object} [options.imports=_.templateSettings.imports]\n * An object to import into the template as free variables.\n * @param {RegExp} [options.interpolate=_.templateSettings.interpolate]\n * The \"interpolate\" delimiter.\n * @param {string} [options.sourceURL='lodash.templateSources[n]']\n * The sourceURL of the compiled template.\n * @param {string} [options.variable='obj']\n * The data object variable name.\n * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.\n * @returns {Function} Returns the compiled template function.\n * @example\n *\n * // Use the \"interpolate\" delimiter to create a compiled template.\n * var compiled = _.template('hello <%= user %>!');\n * compiled({ 'user': 'fred' });\n * // => 'hello fred!'\n *\n * // Use the HTML \"escape\" delimiter to escape data property values.\n * var compiled = _.template('<%- value %>');\n * compiled({ 'value': ' +``` + +This bundle can be used with different module systems; it creates global `Ajv` if no module system is found. + +The browser bundle is available on [cdnjs](https://cdnjs.com/libraries/ajv). + +Ajv is tested with these browsers: + +[](https://saucelabs.com/u/epoberezkin) + +__Please note__: some frameworks, e.g. Dojo, may redefine global require in such way that is not compatible with CommonJS module format. In such case Ajv bundle has to be loaded before the framework and then you can use global Ajv (see issue [#234](https://github.com/ajv-validator/ajv/issues/234)). + + +### Ajv and Content Security Policies (CSP) + +If you're using Ajv to compile a schema (the typical use) in a browser document that is loaded with a Content Security Policy (CSP), that policy will require a `script-src` directive that includes the value `'unsafe-eval'`. +:warning: NOTE, however, that `unsafe-eval` is NOT recommended in a secure CSP[[1]](https://developer.chrome.com/extensions/contentSecurityPolicy#relaxing-eval), as it has the potential to open the document to cross-site scripting (XSS) attacks. + +In order to make use of Ajv without easing your CSP, you can [pre-compile a schema using the CLI](https://github.com/ajv-validator/ajv-cli#compile-schemas). This will transpile the schema JSON into a JavaScript file that exports a `validate` function that works simlarly to a schema compiled at runtime. + +Note that pre-compilation of schemas is performed using [ajv-pack](https://github.com/ajv-validator/ajv-pack) and there are [some limitations to the schema features it can compile](https://github.com/ajv-validator/ajv-pack#limitations). A successfully pre-compiled schema is equivalent to the same schema compiled at runtime. + + +## Command line interface + +CLI is available as a separate npm package [ajv-cli](https://github.com/ajv-validator/ajv-cli). It supports: + +- compiling JSON Schemas to test their validity +- BETA: generating standalone module exporting a validation function to be used without Ajv (using [ajv-pack](https://github.com/ajv-validator/ajv-pack)) +- migrate schemas to draft-07 (using [json-schema-migrate](https://github.com/epoberezkin/json-schema-migrate)) +- validating data file(s) against JSON Schema +- testing expected validity of data against JSON Schema +- referenced schemas +- custom meta-schemas +- files in JSON, JSON5, YAML, and JavaScript format +- all Ajv options +- reporting changes in data after validation in [JSON-patch](https://tools.ietf.org/html/rfc6902) format + + +## Validation keywords + +Ajv supports all validation keywords from draft-07 of JSON Schema standard: + +- [type](https://github.com/ajv-validator/ajv/blob/master/KEYWORDS.md#type) +- [for numbers](https://github.com/ajv-validator/ajv/blob/master/KEYWORDS.md#keywords-for-numbers) - maximum, minimum, exclusiveMaximum, exclusiveMinimum, multipleOf +- [for strings](https://github.com/ajv-validator/ajv/blob/master/KEYWORDS.md#keywords-for-strings) - maxLength, minLength, pattern, format +- [for arrays](https://github.com/ajv-validator/ajv/blob/master/KEYWORDS.md#keywords-for-arrays) - maxItems, minItems, uniqueItems, items, additionalItems, [contains](https://github.com/ajv-validator/ajv/blob/master/KEYWORDS.md#contains) +- [for objects](https://github.com/ajv-validator/ajv/blob/master/KEYWORDS.md#keywords-for-objects) - maxProperties, minProperties, required, properties, patternProperties, additionalProperties, dependencies, [propertyNames](https://github.com/ajv-validator/ajv/blob/master/KEYWORDS.md#propertynames) +- [for all types](https://github.com/ajv-validator/ajv/blob/master/KEYWORDS.md#keywords-for-all-types) - enum, [const](https://github.com/ajv-validator/ajv/blob/master/KEYWORDS.md#const) +- [compound keywords](https://github.com/ajv-validator/ajv/blob/master/KEYWORDS.md#compound-keywords) - not, oneOf, anyOf, allOf, [if/then/else](https://github.com/ajv-validator/ajv/blob/master/KEYWORDS.md#ifthenelse) + +With [ajv-keywords](https://github.com/ajv-validator/ajv-keywords) package Ajv also supports validation keywords from [JSON Schema extension proposals](https://github.com/json-schema/json-schema/wiki/v5-Proposals) for JSON Schema standard: + +- [patternRequired](https://github.com/ajv-validator/ajv/blob/master/KEYWORDS.md#patternrequired-proposed) - like `required` but with patterns that some property should match. +- [formatMaximum, formatMinimum, formatExclusiveMaximum, formatExclusiveMinimum](https://github.com/ajv-validator/ajv/blob/master/KEYWORDS.md#formatmaximum--formatminimum-and-exclusiveformatmaximum--exclusiveformatminimum-proposed) - setting limits for date, time, etc. + +See [JSON Schema validation keywords](https://github.com/ajv-validator/ajv/blob/master/KEYWORDS.md) for more details. + + +## Annotation keywords + +JSON Schema specification defines several annotation keywords that describe schema itself but do not perform any validation. + +- `title` and `description`: information about the data represented by that schema +- `$comment` (NEW in draft-07): information for developers. With option `$comment` Ajv logs or passes the comment string to the user-supplied function. See [Options](#options). +- `default`: a default value of the data instance, see [Assigning defaults](#assigning-defaults). +- `examples` (NEW in draft-06): an array of data instances. Ajv does not check the validity of these instances against the schema. +- `readOnly` and `writeOnly` (NEW in draft-07): marks data-instance as read-only or write-only in relation to the source of the data (database, api, etc.). +- `contentEncoding`: [RFC 2045](https://tools.ietf.org/html/rfc2045#section-6.1 ), e.g., "base64". +- `contentMediaType`: [RFC 2046](https://tools.ietf.org/html/rfc2046), e.g., "image/png". + +__Please note__: Ajv does not implement validation of the keywords `examples`, `contentEncoding` and `contentMediaType` but it reserves them. If you want to create a plugin that implements some of them, it should remove these keywords from the instance. + + +## Formats + +Ajv implements formats defined by JSON Schema specification and several other formats. It is recommended NOT to use "format" keyword implementations with untrusted data, as they use potentially unsafe regular expressions - see [ReDoS attack](#redos-attack). + +__Please note__: if you need to use "format" keyword to validate untrusted data, you MUST assess their suitability and safety for your validation scenarios. + +The following formats are implemented for string validation with "format" keyword: + +- _date_: full-date according to [RFC3339](http://tools.ietf.org/html/rfc3339#section-5.6). +- _time_: time with optional time-zone. +- _date-time_: date-time from the same source (time-zone is mandatory). `date`, `time` and `date-time` validate ranges in `full` mode and only regexp in `fast` mode (see [options](#options)). +- _uri_: full URI. +- _uri-reference_: URI reference, including full and relative URIs. +- _uri-template_: URI template according to [RFC6570](https://tools.ietf.org/html/rfc6570) +- _url_ (deprecated): [URL record](https://url.spec.whatwg.org/#concept-url). +- _email_: email address. +- _hostname_: host name according to [RFC1034](http://tools.ietf.org/html/rfc1034#section-3.5). +- _ipv4_: IP address v4. +- _ipv6_: IP address v6. +- _regex_: tests whether a string is a valid regular expression by passing it to RegExp constructor. +- _uuid_: Universally Unique IDentifier according to [RFC4122](http://tools.ietf.org/html/rfc4122). +- _json-pointer_: JSON-pointer according to [RFC6901](https://tools.ietf.org/html/rfc6901). +- _relative-json-pointer_: relative JSON-pointer according to [this draft](http://tools.ietf.org/html/draft-luff-relative-json-pointer-00). + +__Please note__: JSON Schema draft-07 also defines formats `iri`, `iri-reference`, `idn-hostname` and `idn-email` for URLs, hostnames and emails with international characters. Ajv does not implement these formats. If you create Ajv plugin that implements them please make a PR to mention this plugin here. + +There are two modes of format validation: `fast` and `full`. This mode affects formats `date`, `time`, `date-time`, `uri`, `uri-reference`, and `email`. See [Options](#options) for details. + +You can add additional formats and replace any of the formats above using [addFormat](#api-addformat) method. + +The option `unknownFormats` allows changing the default behaviour when an unknown format is encountered. In this case Ajv can either fail schema compilation (default) or ignore it (default in versions before 5.0.0). You also can allow specific format(s) that will be ignored. See [Options](#options) for details. + +You can find regular expressions used for format validation and the sources that were used in [formats.js](https://github.com/ajv-validator/ajv/blob/master/lib/compile/formats.js). + + +## Combining schemas with $ref + +You can structure your validation logic across multiple schema files and have schemas reference each other using `$ref` keyword. + +Example: + +```javascript +var schema = { + "$id": "http://example.com/schemas/schema.json", + "type": "object", + "properties": { + "foo": { "$ref": "defs.json#/definitions/int" }, + "bar": { "$ref": "defs.json#/definitions/str" } + } +}; + +var defsSchema = { + "$id": "http://example.com/schemas/defs.json", + "definitions": { + "int": { "type": "integer" }, + "str": { "type": "string" } + } +}; +``` + +Now to compile your schema you can either pass all schemas to Ajv instance: + +```javascript +var ajv = new Ajv({schemas: [schema, defsSchema]}); +var validate = ajv.getSchema('http://example.com/schemas/schema.json'); +``` + +or use `addSchema` method: + +```javascript +var ajv = new Ajv; +var validate = ajv.addSchema(defsSchema) + .compile(schema); +``` + +See [Options](#options) and [addSchema](#api) method. + +__Please note__: +- `$ref` is resolved as the uri-reference using schema $id as the base URI (see the example). +- References can be recursive (and mutually recursive) to implement the schemas for different data structures (such as linked lists, trees, graphs, etc.). +- You don't have to host your schema files at the URIs that you use as schema $id. These URIs are only used to identify the schemas, and according to JSON Schema specification validators should not expect to be able to download the schemas from these URIs. +- The actual location of the schema file in the file system is not used. +- You can pass the identifier of the schema as the second parameter of `addSchema` method or as a property name in `schemas` option. This identifier can be used instead of (or in addition to) schema $id. +- You cannot have the same $id (or the schema identifier) used for more than one schema - the exception will be thrown. +- You can implement dynamic resolution of the referenced schemas using `compileAsync` method. In this way you can store schemas in any system (files, web, database, etc.) and reference them without explicitly adding to Ajv instance. See [Asynchronous schema compilation](#asynchronous-schema-compilation). + + +## $data reference + +With `$data` option you can use values from the validated data as the values for the schema keywords. See [proposal](https://github.com/json-schema-org/json-schema-spec/issues/51) for more information about how it works. + +`$data` reference is supported in the keywords: const, enum, format, maximum/minimum, exclusiveMaximum / exclusiveMinimum, maxLength / minLength, maxItems / minItems, maxProperties / minProperties, formatMaximum / formatMinimum, formatExclusiveMaximum / formatExclusiveMinimum, multipleOf, pattern, required, uniqueItems. + +The value of "$data" should be a [JSON-pointer](https://tools.ietf.org/html/rfc6901) to the data (the root is always the top level data object, even if the $data reference is inside a referenced subschema) or a [relative JSON-pointer](http://tools.ietf.org/html/draft-luff-relative-json-pointer-00) (it is relative to the current point in data; if the $data reference is inside a referenced subschema it cannot point to the data outside of the root level for this subschema). + +Examples. + +This schema requires that the value in property `smaller` is less or equal than the value in the property larger: + +```javascript +var ajv = new Ajv({$data: true}); + +var schema = { + "properties": { + "smaller": { + "type": "number", + "maximum": { "$data": "1/larger" } + }, + "larger": { "type": "number" } + } +}; + +var validData = { + smaller: 5, + larger: 7 +}; + +ajv.validate(schema, validData); // true +``` + +This schema requires that the properties have the same format as their field names: + +```javascript +var schema = { + "additionalProperties": { + "type": "string", + "format": { "$data": "0#" } + } +}; + +var validData = { + 'date-time': '1963-06-19T08:30:06.283185Z', + email: 'joe.bloggs@example.com' +} +``` + +`$data` reference is resolved safely - it won't throw even if some property is undefined. If `$data` resolves to `undefined` the validation succeeds (with the exclusion of `const` keyword). If `$data` resolves to incorrect type (e.g. not "number" for maximum keyword) the validation fails. + + +## $merge and $patch keywords + +With the package [ajv-merge-patch](https://github.com/ajv-validator/ajv-merge-patch) you can use the keywords `$merge` and `$patch` that allow extending JSON Schemas with patches using formats [JSON Merge Patch (RFC 7396)](https://tools.ietf.org/html/rfc7396) and [JSON Patch (RFC 6902)](https://tools.ietf.org/html/rfc6902). + +To add keywords `$merge` and `$patch` to Ajv instance use this code: + +```javascript +require('ajv-merge-patch')(ajv); +``` + +Examples. + +Using `$merge`: + +```json +{ + "$merge": { + "source": { + "type": "object", + "properties": { "p": { "type": "string" } }, + "additionalProperties": false + }, + "with": { + "properties": { "q": { "type": "number" } } + } + } +} +``` + +Using `$patch`: + +```json +{ + "$patch": { + "source": { + "type": "object", + "properties": { "p": { "type": "string" } }, + "additionalProperties": false + }, + "with": [ + { "op": "add", "path": "/properties/q", "value": { "type": "number" } } + ] + } +} +``` + +The schemas above are equivalent to this schema: + +```json +{ + "type": "object", + "properties": { + "p": { "type": "string" }, + "q": { "type": "number" } + }, + "additionalProperties": false +} +``` + +The properties `source` and `with` in the keywords `$merge` and `$patch` can use absolute or relative `$ref` to point to other schemas previously added to the Ajv instance or to the fragments of the current schema. + +See the package [ajv-merge-patch](https://github.com/ajv-validator/ajv-merge-patch) for more information. + + +## Defining custom keywords + +The advantages of using custom keywords are: + +- allow creating validation scenarios that cannot be expressed using JSON Schema +- simplify your schemas +- help bringing a bigger part of the validation logic to your schemas +- make your schemas more expressive, less verbose and closer to your application domain +- implement custom data processors that modify your data (`modifying` option MUST be used in keyword definition) and/or create side effects while the data is being validated + +If a keyword is used only for side-effects and its validation result is pre-defined, use option `valid: true/false` in keyword definition to simplify both generated code (no error handling in case of `valid: true`) and your keyword functions (no need to return any validation result). + +The concerns you have to be aware of when extending JSON Schema standard with custom keywords are the portability and understanding of your schemas. You will have to support these custom keywords on other platforms and to properly document these keywords so that everybody can understand them in your schemas. + +You can define custom keywords with [addKeyword](#api-addkeyword) method. Keywords are defined on the `ajv` instance level - new instances will not have previously defined keywords. + +Ajv allows defining keywords with: +- validation function +- compilation function +- macro function +- inline compilation function that should return code (as string) that will be inlined in the currently compiled schema. + +Example. `range` and `exclusiveRange` keywords using compiled schema: + +```javascript +ajv.addKeyword('range', { + type: 'number', + compile: function (sch, parentSchema) { + var min = sch[0]; + var max = sch[1]; + + return parentSchema.exclusiveRange === true + ? function (data) { return data > min && data < max; } + : function (data) { return data >= min && data <= max; } + } +}); + +var schema = { "range": [2, 4], "exclusiveRange": true }; +var validate = ajv.compile(schema); +console.log(validate(2.01)); // true +console.log(validate(3.99)); // true +console.log(validate(2)); // false +console.log(validate(4)); // false +``` + +Several custom keywords (typeof, instanceof, range and propertyNames) are defined in [ajv-keywords](https://github.com/ajv-validator/ajv-keywords) package - they can be used for your schemas and as a starting point for your own custom keywords. + +See [Defining custom keywords](https://github.com/ajv-validator/ajv/blob/master/CUSTOM.md) for more details. + + +## Asynchronous schema compilation + +During asynchronous compilation remote references are loaded using supplied function. See `compileAsync` [method](#api-compileAsync) and `loadSchema` [option](#options). + +Example: + +```javascript +var ajv = new Ajv({ loadSchema: loadSchema }); + +ajv.compileAsync(schema).then(function (validate) { + var valid = validate(data); + // ... +}); + +function loadSchema(uri) { + return request.json(uri).then(function (res) { + if (res.statusCode >= 400) + throw new Error('Loading error: ' + res.statusCode); + return res.body; + }); +} +``` + +__Please note__: [Option](#options) `missingRefs` should NOT be set to `"ignore"` or `"fail"` for asynchronous compilation to work. + + +## Asynchronous validation + +Example in Node.js REPL: https://tonicdev.com/esp/ajv-asynchronous-validation + +You can define custom formats and keywords that perform validation asynchronously by accessing database or some other service. You should add `async: true` in the keyword or format definition (see [addFormat](#api-addformat), [addKeyword](#api-addkeyword) and [Defining custom keywords](#defining-custom-keywords)). + +If your schema uses asynchronous formats/keywords or refers to some schema that contains them it should have `"$async": true` keyword so that Ajv can compile it correctly. If asynchronous format/keyword or reference to asynchronous schema is used in the schema without `$async` keyword Ajv will throw an exception during schema compilation. + +__Please note__: all asynchronous subschemas that are referenced from the current or other schemas should have `"$async": true` keyword as well, otherwise the schema compilation will fail. + +Validation function for an asynchronous custom format/keyword should return a promise that resolves with `true` or `false` (or rejects with `new Ajv.ValidationError(errors)` if you want to return custom errors from the keyword function). + +Ajv compiles asynchronous schemas to [es7 async functions](http://tc39.github.io/ecmascript-asyncawait/) that can optionally be transpiled with [nodent](https://github.com/MatAtBread/nodent). Async functions are supported in Node.js 7+ and all modern browsers. You can also supply any other transpiler as a function via `processCode` option. See [Options](#options). + +The compiled validation function has `$async: true` property (if the schema is asynchronous), so you can differentiate these functions if you are using both synchronous and asynchronous schemas. + +Validation result will be a promise that resolves with validated data or rejects with an exception `Ajv.ValidationError` that contains the array of validation errors in `errors` property. + + +Example: + +```javascript +var ajv = new Ajv; +// require('ajv-async')(ajv); + +ajv.addKeyword('idExists', { + async: true, + type: 'number', + validate: checkIdExists +}); + + +function checkIdExists(schema, data) { + return knex(schema.table) + .select('id') + .where('id', data) + .then(function (rows) { + return !!rows.length; // true if record is found + }); +} + +var schema = { + "$async": true, + "properties": { + "userId": { + "type": "integer", + "idExists": { "table": "users" } + }, + "postId": { + "type": "integer", + "idExists": { "table": "posts" } + } + } +}; + +var validate = ajv.compile(schema); + +validate({ userId: 1, postId: 19 }) +.then(function (data) { + console.log('Data is valid', data); // { userId: 1, postId: 19 } +}) +.catch(function (err) { + if (!(err instanceof Ajv.ValidationError)) throw err; + // data is invalid + console.log('Validation errors:', err.errors); +}); +``` + +### Using transpilers with asynchronous validation functions. + +[ajv-async](https://github.com/ajv-validator/ajv-async) uses [nodent](https://github.com/MatAtBread/nodent) to transpile async functions. To use another transpiler you should separately install it (or load its bundle in the browser). + + +#### Using nodent + +```javascript +var ajv = new Ajv; +require('ajv-async')(ajv); +// in the browser if you want to load ajv-async bundle separately you can: +// window.ajvAsync(ajv); +var validate = ajv.compile(schema); // transpiled es7 async function +validate(data).then(successFunc).catch(errorFunc); +``` + + +#### Using other transpilers + +```javascript +var ajv = new Ajv({ processCode: transpileFunc }); +var validate = ajv.compile(schema); // transpiled es7 async function +validate(data).then(successFunc).catch(errorFunc); +``` + +See [Options](#options). + + +## Security considerations + +JSON Schema, if properly used, can replace data sanitisation. It doesn't replace other API security considerations. It also introduces additional security aspects to consider. + + +##### Security contact + +To report a security vulnerability, please use the +[Tidelift security contact](https://tidelift.com/security). +Tidelift will coordinate the fix and disclosure. Please do NOT report security vulnerabilities via GitHub issues. + + +##### Untrusted schemas + +Ajv treats JSON schemas as trusted as your application code. This security model is based on the most common use case, when the schemas are static and bundled together with the application. + +If your schemas are received from untrusted sources (or generated from untrusted data) there are several scenarios you need to prevent: +- compiling schemas can cause stack overflow (if they are too deep) +- compiling schemas can be slow (e.g. [#557](https://github.com/ajv-validator/ajv/issues/557)) +- validating certain data can be slow + +It is difficult to predict all the scenarios, but at the very least it may help to limit the size of untrusted schemas (e.g. limit JSON string length) and also the maximum schema object depth (that can be high for relatively small JSON strings). You also may want to mitigate slow regular expressions in `pattern` and `patternProperties` keywords. + +Regardless the measures you take, using untrusted schemas increases security risks. + + +##### Circular references in JavaScript objects + +Ajv does not support schemas and validated data that have circular references in objects. See [issue #802](https://github.com/ajv-validator/ajv/issues/802). + +An attempt to compile such schemas or validate such data would cause stack overflow (or will not complete in case of asynchronous validation). Depending on the parser you use, untrusted data can lead to circular references. + + +##### Security risks of trusted schemas + +Some keywords in JSON Schemas can lead to very slow validation for certain data. These keywords include (but may be not limited to): + +- `pattern` and `format` for large strings - in some cases using `maxLength` can help mitigate it, but certain regular expressions can lead to exponential validation time even with relatively short strings (see [ReDoS attack](#redos-attack)). +- `patternProperties` for large property names - use `propertyNames` to mitigate, but some regular expressions can have exponential evaluation time as well. +- `uniqueItems` for large non-scalar arrays - use `maxItems` to mitigate + +__Please note__: The suggestions above to prevent slow validation would only work if you do NOT use `allErrors: true` in production code (using it would continue validation after validation errors). + +You can validate your JSON schemas against [this meta-schema](https://github.com/ajv-validator/ajv/blob/master/lib/refs/json-schema-secure.json) to check that these recommendations are followed: + +```javascript +const isSchemaSecure = ajv.compile(require('ajv/lib/refs/json-schema-secure.json')); + +const schema1 = {format: 'email'}; +isSchemaSecure(schema1); // false + +const schema2 = {format: 'email', maxLength: MAX_LENGTH}; +isSchemaSecure(schema2); // true +``` + +__Please note__: following all these recommendation is not a guarantee that validation of untrusted data is safe - it can still lead to some undesirable results. + + +##### Content Security Policies (CSP) +See [Ajv and Content Security Policies (CSP)](#ajv-and-content-security-policies-csp) + + +## ReDoS attack + +Certain regular expressions can lead to the exponential evaluation time even with relatively short strings. + +Please assess the regular expressions you use in the schemas on their vulnerability to this attack - see [safe-regex](https://github.com/substack/safe-regex), for example. + +__Please note__: some formats that Ajv implements use [regular expressions](https://github.com/ajv-validator/ajv/blob/master/lib/compile/formats.js) that can be vulnerable to ReDoS attack, so if you use Ajv to validate data from untrusted sources __it is strongly recommended__ to consider the following: + +- making assessment of "format" implementations in Ajv. +- using `format: 'fast'` option that simplifies some of the regular expressions (although it does not guarantee that they are safe). +- replacing format implementations provided by Ajv with your own implementations of "format" keyword that either uses different regular expressions or another approach to format validation. Please see [addFormat](#api-addformat) method. +- disabling format validation by ignoring "format" keyword with option `format: false` + +Whatever mitigation you choose, please assume all formats provided by Ajv as potentially unsafe and make your own assessment of their suitability for your validation scenarios. + + +## Filtering data + +With [option `removeAdditional`](#options) (added by [andyscott](https://github.com/andyscott)) you can filter data during the validation. + +This option modifies original data. + +Example: + +```javascript +var ajv = new Ajv({ removeAdditional: true }); +var schema = { + "additionalProperties": false, + "properties": { + "foo": { "type": "number" }, + "bar": { + "additionalProperties": { "type": "number" }, + "properties": { + "baz": { "type": "string" } + } + } + } +} + +var data = { + "foo": 0, + "additional1": 1, // will be removed; `additionalProperties` == false + "bar": { + "baz": "abc", + "additional2": 2 // will NOT be removed; `additionalProperties` != false + }, +} + +var validate = ajv.compile(schema); + +console.log(validate(data)); // true +console.log(data); // { "foo": 0, "bar": { "baz": "abc", "additional2": 2 } +``` + +If `removeAdditional` option in the example above were `"all"` then both `additional1` and `additional2` properties would have been removed. + +If the option were `"failing"` then property `additional1` would have been removed regardless of its value and property `additional2` would have been removed only if its value were failing the schema in the inner `additionalProperties` (so in the example above it would have stayed because it passes the schema, but any non-number would have been removed). + +__Please note__: If you use `removeAdditional` option with `additionalProperties` keyword inside `anyOf`/`oneOf` keywords your validation can fail with this schema, for example: + +```json +{ + "type": "object", + "oneOf": [ + { + "properties": { + "foo": { "type": "string" } + }, + "required": [ "foo" ], + "additionalProperties": false + }, + { + "properties": { + "bar": { "type": "integer" } + }, + "required": [ "bar" ], + "additionalProperties": false + } + ] +} +``` + +The intention of the schema above is to allow objects with either the string property "foo" or the integer property "bar", but not with both and not with any other properties. + +With the option `removeAdditional: true` the validation will pass for the object `{ "foo": "abc"}` but will fail for the object `{"bar": 1}`. It happens because while the first subschema in `oneOf` is validated, the property `bar` is removed because it is an additional property according to the standard (because it is not included in `properties` keyword in the same schema). + +While this behaviour is unexpected (issues [#129](https://github.com/ajv-validator/ajv/issues/129), [#134](https://github.com/ajv-validator/ajv/issues/134)), it is correct. To have the expected behaviour (both objects are allowed and additional properties are removed) the schema has to be refactored in this way: + +```json +{ + "type": "object", + "properties": { + "foo": { "type": "string" }, + "bar": { "type": "integer" } + }, + "additionalProperties": false, + "oneOf": [ + { "required": [ "foo" ] }, + { "required": [ "bar" ] } + ] +} +``` + +The schema above is also more efficient - it will compile into a faster function. + + +## Assigning defaults + +With [option `useDefaults`](#options) Ajv will assign values from `default` keyword in the schemas of `properties` and `items` (when it is the array of schemas) to the missing properties and items. + +With the option value `"empty"` properties and items equal to `null` or `""` (empty string) will be considered missing and assigned defaults. + +This option modifies original data. + +__Please note__: the default value is inserted in the generated validation code as a literal, so the value inserted in the data will be the deep clone of the default in the schema. + + +Example 1 (`default` in `properties`): + +```javascript +var ajv = new Ajv({ useDefaults: true }); +var schema = { + "type": "object", + "properties": { + "foo": { "type": "number" }, + "bar": { "type": "string", "default": "baz" } + }, + "required": [ "foo", "bar" ] +}; + +var data = { "foo": 1 }; + +var validate = ajv.compile(schema); + +console.log(validate(data)); // true +console.log(data); // { "foo": 1, "bar": "baz" } +``` + +Example 2 (`default` in `items`): + +```javascript +var schema = { + "type": "array", + "items": [ + { "type": "number" }, + { "type": "string", "default": "foo" } + ] +} + +var data = [ 1 ]; + +var validate = ajv.compile(schema); + +console.log(validate(data)); // true +console.log(data); // [ 1, "foo" ] +``` + +`default` keywords in other cases are ignored: + +- not in `properties` or `items` subschemas +- in schemas inside `anyOf`, `oneOf` and `not` (see [#42](https://github.com/ajv-validator/ajv/issues/42)) +- in `if` subschema of `switch` keyword +- in schemas generated by custom macro keywords + +The [`strictDefaults` option](#options) customizes Ajv's behavior for the defaults that Ajv ignores (`true` raises an error, and `"log"` outputs a warning). + + +## Coercing data types + +When you are validating user inputs all your data properties are usually strings. The option `coerceTypes` allows you to have your data types coerced to the types specified in your schema `type` keywords, both to pass the validation and to use the correctly typed data afterwards. + +This option modifies original data. + +__Please note__: if you pass a scalar value to the validating function its type will be coerced and it will pass the validation, but the value of the variable you pass won't be updated because scalars are passed by value. + + +Example 1: + +```javascript +var ajv = new Ajv({ coerceTypes: true }); +var schema = { + "type": "object", + "properties": { + "foo": { "type": "number" }, + "bar": { "type": "boolean" } + }, + "required": [ "foo", "bar" ] +}; + +var data = { "foo": "1", "bar": "false" }; + +var validate = ajv.compile(schema); + +console.log(validate(data)); // true +console.log(data); // { "foo": 1, "bar": false } +``` + +Example 2 (array coercions): + +```javascript +var ajv = new Ajv({ coerceTypes: 'array' }); +var schema = { + "properties": { + "foo": { "type": "array", "items": { "type": "number" } }, + "bar": { "type": "boolean" } + } +}; + +var data = { "foo": "1", "bar": ["false"] }; + +var validate = ajv.compile(schema); + +console.log(validate(data)); // true +console.log(data); // { "foo": [1], "bar": false } +``` + +The coercion rules, as you can see from the example, are different from JavaScript both to validate user input as expected and to have the coercion reversible (to correctly validate cases where different types are defined in subschemas of "anyOf" and other compound keywords). + +See [Coercion rules](https://github.com/ajv-validator/ajv/blob/master/COERCION.md) for details. + + +## API + +##### new Ajv(Object options) -> Object + +Create Ajv instance. + + +##### .compile(Object schema) -> Function<Object data> + +Generate validating function and cache the compiled schema for future use. + +Validating function returns a boolean value. This function has properties `errors` and `schema`. Errors encountered during the last validation are assigned to `errors` property (it is assigned `null` if there was no errors). `schema` property contains the reference to the original schema. + +The schema passed to this method will be validated against meta-schema unless `validateSchema` option is false. If schema is invalid, an error will be thrown. See [options](#options). + + +##### .compileAsync(Object schema [, Boolean meta] [, Function callback]) -> Promise + +Asynchronous version of `compile` method that loads missing remote schemas using asynchronous function in `options.loadSchema`. This function returns a Promise that resolves to a validation function. An optional callback passed to `compileAsync` will be called with 2 parameters: error (or null) and validating function. The returned promise will reject (and the callback will be called with an error) when: + +- missing schema can't be loaded (`loadSchema` returns a Promise that rejects). +- a schema containing a missing reference is loaded, but the reference cannot be resolved. +- schema (or some loaded/referenced schema) is invalid. + +The function compiles schema and loads the first missing schema (or meta-schema) until all missing schemas are loaded. + +You can asynchronously compile meta-schema by passing `true` as the second parameter. + +See example in [Asynchronous compilation](#asynchronous-schema-compilation). + + +##### .validate(Object schema|String key|String ref, data) -> Boolean + +Validate data using passed schema (it will be compiled and cached). + +Instead of the schema you can use the key that was previously passed to `addSchema`, the schema id if it was present in the schema or any previously resolved reference. + +Validation errors will be available in the `errors` property of Ajv instance (`null` if there were no errors). + +__Please note__: every time this method is called the errors are overwritten so you need to copy them to another variable if you want to use them later. + +If the schema is asynchronous (has `$async` keyword on the top level) this method returns a Promise. See [Asynchronous validation](#asynchronous-validation). + + +##### .addSchema(Array<Object>|Object schema [, String key]) -> Ajv + +Add schema(s) to validator instance. This method does not compile schemas (but it still validates them). Because of that dependencies can be added in any order and circular dependencies are supported. It also prevents unnecessary compilation of schemas that are containers for other schemas but not used as a whole. + +Array of schemas can be passed (schemas should have ids), the second parameter will be ignored. + +Key can be passed that can be used to reference the schema and will be used as the schema id if there is no id inside the schema. If the key is not passed, the schema id will be used as the key. + + +Once the schema is added, it (and all the references inside it) can be referenced in other schemas and used to validate data. + +Although `addSchema` does not compile schemas, explicit compilation is not required - the schema will be compiled when it is used first time. + +By default the schema is validated against meta-schema before it is added, and if the schema does not pass validation the exception is thrown. This behaviour is controlled by `validateSchema` option. + +__Please note__: Ajv uses the [method chaining syntax](https://en.wikipedia.org/wiki/Method_chaining) for all methods with the prefix `add*` and `remove*`. +This allows you to do nice things like the following. + +```javascript +var validate = new Ajv().addSchema(schema).addFormat(name, regex).getSchema(uri); +``` + +##### .addMetaSchema(Array<Object>|Object schema [, String key]) -> Ajv + +Adds meta schema(s) that can be used to validate other schemas. That function should be used instead of `addSchema` because there may be instance options that would compile a meta schema incorrectly (at the moment it is `removeAdditional` option). + +There is no need to explicitly add draft-07 meta schema (http://json-schema.org/draft-07/schema) - it is added by default, unless option `meta` is set to `false`. You only need to use it if you have a changed meta-schema that you want to use to validate your schemas. See `validateSchema`. + + +##### .validateSchema(Object schema) -> Boolean + +Validates schema. This method should be used to validate schemas rather than `validate` due to the inconsistency of `uri` format in JSON Schema standard. + +By default this method is called automatically when the schema is added, so you rarely need to use it directly. + +If schema doesn't have `$schema` property, it is validated against draft 6 meta-schema (option `meta` should not be false). + +If schema has `$schema` property, then the schema with this id (that should be previously added) is used to validate passed schema. + +Errors will be available at `ajv.errors`. + + +##### .getSchema(String key) -> Function<Object data> + +Retrieve compiled schema previously added with `addSchema` by the key passed to `addSchema` or by its full reference (id). The returned validating function has `schema` property with the reference to the original schema. + + +##### .removeSchema([Object schema|String key|String ref|RegExp pattern]) -> Ajv + +Remove added/cached schema. Even if schema is referenced by other schemas it can be safely removed as dependent schemas have local references. + +Schema can be removed using: +- key passed to `addSchema` +- it's full reference (id) +- RegExp that should match schema id or key (meta-schemas won't be removed) +- actual schema object that will be stable-stringified to remove schema from cache + +If no parameter is passed all schemas but meta-schemas will be removed and the cache will be cleared. + + +##### .addFormat(String name, String|RegExp|Function|Object format) -> Ajv + +Add custom format to validate strings or numbers. It can also be used to replace pre-defined formats for Ajv instance. + +Strings are converted to RegExp. + +Function should return validation result as `true` or `false`. + +If object is passed it should have properties `validate`, `compare` and `async`: + +- _validate_: a string, RegExp or a function as described above. +- _compare_: an optional comparison function that accepts two strings and compares them according to the format meaning. This function is used with keywords `formatMaximum`/`formatMinimum` (defined in [ajv-keywords](https://github.com/ajv-validator/ajv-keywords) package). It should return `1` if the first value is bigger than the second value, `-1` if it is smaller and `0` if it is equal. +- _async_: an optional `true` value if `validate` is an asynchronous function; in this case it should return a promise that resolves with a value `true` or `false`. +- _type_: an optional type of data that the format applies to. It can be `"string"` (default) or `"number"` (see https://github.com/ajv-validator/ajv/issues/291#issuecomment-259923858). If the type of data is different, the validation will pass. + +Custom formats can be also added via `formats` option. + + +##### .addKeyword(String keyword, Object definition) -> Ajv + +Add custom validation keyword to Ajv instance. + +Keyword should be different from all standard JSON Schema keywords and different from previously defined keywords. There is no way to redefine keywords or to remove keyword definition from the instance. + +Keyword must start with a letter, `_` or `$`, and may continue with letters, numbers, `_`, `$`, or `-`. +It is recommended to use an application-specific prefix for keywords to avoid current and future name collisions. + +Example Keywords: +- `"xyz-example"`: valid, and uses prefix for the xyz project to avoid name collisions. +- `"example"`: valid, but not recommended as it could collide with future versions of JSON Schema etc. +- `"3-example"`: invalid as numbers are not allowed to be the first character in a keyword + +Keyword definition is an object with the following properties: + +- _type_: optional string or array of strings with data type(s) that the keyword applies to. If not present, the keyword will apply to all types. +- _validate_: validating function +- _compile_: compiling function +- _macro_: macro function +- _inline_: compiling function that returns code (as string) +- _schema_: an optional `false` value used with "validate" keyword to not pass schema +- _metaSchema_: an optional meta-schema for keyword schema +- _dependencies_: an optional list of properties that must be present in the parent schema - it will be checked during schema compilation +- _modifying_: `true` MUST be passed if keyword modifies data +- _statements_: `true` can be passed in case inline keyword generates statements (as opposed to expression) +- _valid_: pass `true`/`false` to pre-define validation result, the result returned from validation function will be ignored. This option cannot be used with macro keywords. +- _$data_: an optional `true` value to support [$data reference](#data-reference) as the value of custom keyword. The reference will be resolved at validation time. If the keyword has meta-schema it would be extended to allow $data and it will be used to validate the resolved value. Supporting $data reference requires that keyword has validating function (as the only option or in addition to compile, macro or inline function). +- _async_: an optional `true` value if the validation function is asynchronous (whether it is compiled or passed in _validate_ property); in this case it should return a promise that resolves with a value `true` or `false`. This option is ignored in case of "macro" and "inline" keywords. +- _errors_: an optional boolean or string `"full"` indicating whether keyword returns errors. If this property is not set Ajv will determine if the errors were set in case of failed validation. + +_compile_, _macro_ and _inline_ are mutually exclusive, only one should be used at a time. _validate_ can be used separately or in addition to them to support $data reference. + +__Please note__: If the keyword is validating data type that is different from the type(s) in its definition, the validation function will not be called (and expanded macro will not be used), so there is no need to check for data type inside validation function or inside schema returned by macro function (unless you want to enforce a specific type and for some reason do not want to use a separate `type` keyword for that). In the same way as standard keywords work, if the keyword does not apply to the data type being validated, the validation of this keyword will succeed. + +See [Defining custom keywords](#defining-custom-keywords) for more details. + + +##### .getKeyword(String keyword) -> Object|Boolean + +Returns custom keyword definition, `true` for pre-defined keywords and `false` if the keyword is unknown. + + +##### .removeKeyword(String keyword) -> Ajv + +Removes custom or pre-defined keyword so you can redefine them. + +While this method can be used to extend pre-defined keywords, it can also be used to completely change their meaning - it may lead to unexpected results. + +__Please note__: schemas compiled before the keyword is removed will continue to work without changes. To recompile schemas use `removeSchema` method and compile them again. + + +##### .errorsText([Array<Object> errors [, Object options]]) -> String + +Returns the text with all errors in a String. + +Options can have properties `separator` (string used to separate errors, ", " by default) and `dataVar` (the variable name that dataPaths are prefixed with, "data" by default). + + +## Options + +Defaults: + +```javascript +{ + // validation and reporting options: + $data: false, + allErrors: false, + verbose: false, + $comment: false, // NEW in Ajv version 6.0 + jsonPointers: false, + uniqueItems: true, + unicode: true, + nullable: false, + format: 'fast', + formats: {}, + unknownFormats: true, + schemas: {}, + logger: undefined, + // referenced schema options: + schemaId: '$id', + missingRefs: true, + extendRefs: 'ignore', // recommended 'fail' + loadSchema: undefined, // function(uri: string): Promise {} + // options to modify validated data: + removeAdditional: false, + useDefaults: false, + coerceTypes: false, + // strict mode options + strictDefaults: false, + strictKeywords: false, + strictNumbers: false, + // asynchronous validation options: + transpile: undefined, // requires ajv-async package + // advanced options: + meta: true, + validateSchema: true, + addUsedSchema: true, + inlineRefs: true, + passContext: false, + loopRequired: Infinity, + ownProperties: false, + multipleOfPrecision: false, + errorDataPath: 'object', // deprecated + messages: true, + sourceCode: false, + processCode: undefined, // function (str: string, schema: object): string {} + cache: new Cache, + serialize: undefined +} +``` + +##### Validation and reporting options + +- _$data_: support [$data references](#data-reference). Draft 6 meta-schema that is added by default will be extended to allow them. If you want to use another meta-schema you need to use $dataMetaSchema method to add support for $data reference. See [API](#api). +- _allErrors_: check all rules collecting all errors. Default is to return after the first error. +- _verbose_: include the reference to the part of the schema (`schema` and `parentSchema`) and validated data in errors (false by default). +- _$comment_ (NEW in Ajv version 6.0): log or pass the value of `$comment` keyword to a function. Option values: + - `false` (default): ignore $comment keyword. + - `true`: log the keyword value to console. + - function: pass the keyword value, its schema path and root schema to the specified function +- _jsonPointers_: set `dataPath` property of errors using [JSON Pointers](https://tools.ietf.org/html/rfc6901) instead of JavaScript property access notation. +- _uniqueItems_: validate `uniqueItems` keyword (true by default). +- _unicode_: calculate correct length of strings with unicode pairs (true by default). Pass `false` to use `.length` of strings that is faster, but gives "incorrect" lengths of strings with unicode pairs - each unicode pair is counted as two characters. +- _nullable_: support keyword "nullable" from [Open API 3 specification](https://swagger.io/docs/specification/data-models/data-types/). +- _format_: formats validation mode. Option values: + - `"fast"` (default) - simplified and fast validation (see [Formats](#formats) for details of which formats are available and affected by this option). + - `"full"` - more restrictive and slow validation. E.g., 25:00:00 and 2015/14/33 will be invalid time and date in 'full' mode but it will be valid in 'fast' mode. + - `false` - ignore all format keywords. +- _formats_: an object with custom formats. Keys and values will be passed to `addFormat` method. +- _keywords_: an object with custom keywords. Keys and values will be passed to `addKeyword` method. +- _unknownFormats_: handling of unknown formats. Option values: + - `true` (default) - if an unknown format is encountered the exception is thrown during schema compilation. If `format` keyword value is [$data reference](#data-reference) and it is unknown the validation will fail. + - `[String]` - an array of unknown format names that will be ignored. This option can be used to allow usage of third party schemas with format(s) for which you don't have definitions, but still fail if another unknown format is used. If `format` keyword value is [$data reference](#data-reference) and it is not in this array the validation will fail. + - `"ignore"` - to log warning during schema compilation and always pass validation (the default behaviour in versions before 5.0.0). This option is not recommended, as it allows to mistype format name and it won't be validated without any error message. This behaviour is required by JSON Schema specification. +- _schemas_: an array or object of schemas that will be added to the instance. In case you pass the array the schemas must have IDs in them. When the object is passed the method `addSchema(value, key)` will be called for each schema in this object. +- _logger_: sets the logging method. Default is the global `console` object that should have methods `log`, `warn` and `error`. See [Error logging](#error-logging). Option values: + - custom logger - it should have methods `log`, `warn` and `error`. If any of these methods is missing an exception will be thrown. + - `false` - logging is disabled. + + +##### Referenced schema options + +- _schemaId_: this option defines which keywords are used as schema URI. Option value: + - `"$id"` (default) - only use `$id` keyword as schema URI (as specified in JSON Schema draft-06/07), ignore `id` keyword (if it is present a warning will be logged). + - `"id"` - only use `id` keyword as schema URI (as specified in JSON Schema draft-04), ignore `$id` keyword (if it is present a warning will be logged). + - `"auto"` - use both `$id` and `id` keywords as schema URI. If both are present (in the same schema object) and different the exception will be thrown during schema compilation. +- _missingRefs_: handling of missing referenced schemas. Option values: + - `true` (default) - if the reference cannot be resolved during compilation the exception is thrown. The thrown error has properties `missingRef` (with hash fragment) and `missingSchema` (without it). Both properties are resolved relative to the current base id (usually schema id, unless it was substituted). + - `"ignore"` - to log error during compilation and always pass validation. + - `"fail"` - to log error and successfully compile schema but fail validation if this rule is checked. +- _extendRefs_: validation of other keywords when `$ref` is present in the schema. Option values: + - `"ignore"` (default) - when `$ref` is used other keywords are ignored (as per [JSON Reference](https://tools.ietf.org/html/draft-pbryan-zyp-json-ref-03#section-3) standard). A warning will be logged during the schema compilation. + - `"fail"` (recommended) - if other validation keywords are used together with `$ref` the exception will be thrown when the schema is compiled. This option is recommended to make sure schema has no keywords that are ignored, which can be confusing. + - `true` - validate all keywords in the schemas with `$ref` (the default behaviour in versions before 5.0.0). +- _loadSchema_: asynchronous function that will be used to load remote schemas when `compileAsync` [method](#api-compileAsync) is used and some reference is missing (option `missingRefs` should NOT be 'fail' or 'ignore'). This function should accept remote schema uri as a parameter and return a Promise that resolves to a schema. See example in [Asynchronous compilation](#asynchronous-schema-compilation). + + +##### Options to modify validated data + +- _removeAdditional_: remove additional properties - see example in [Filtering data](#filtering-data). This option is not used if schema is added with `addMetaSchema` method. Option values: + - `false` (default) - not to remove additional properties + - `"all"` - all additional properties are removed, regardless of `additionalProperties` keyword in schema (and no validation is made for them). + - `true` - only additional properties with `additionalProperties` keyword equal to `false` are removed. + - `"failing"` - additional properties that fail schema validation will be removed (where `additionalProperties` keyword is `false` or schema). +- _useDefaults_: replace missing or undefined properties and items with the values from corresponding `default` keywords. Default behaviour is to ignore `default` keywords. This option is not used if schema is added with `addMetaSchema` method. See examples in [Assigning defaults](#assigning-defaults). Option values: + - `false` (default) - do not use defaults + - `true` - insert defaults by value (object literal is used). + - `"empty"` - in addition to missing or undefined, use defaults for properties and items that are equal to `null` or `""` (an empty string). + - `"shared"` (deprecated) - insert defaults by reference. If the default is an object, it will be shared by all instances of validated data. If you modify the inserted default in the validated data, it will be modified in the schema as well. +- _coerceTypes_: change data type of data to match `type` keyword. See the example in [Coercing data types](#coercing-data-types) and [coercion rules](https://github.com/ajv-validator/ajv/blob/master/COERCION.md). Option values: + - `false` (default) - no type coercion. + - `true` - coerce scalar data types. + - `"array"` - in addition to coercions between scalar types, coerce scalar data to an array with one element and vice versa (as required by the schema). + + +##### Strict mode options + +- _strictDefaults_: report ignored `default` keywords in schemas. Option values: + - `false` (default) - ignored defaults are not reported + - `true` - if an ignored default is present, throw an error + - `"log"` - if an ignored default is present, log warning +- _strictKeywords_: report unknown keywords in schemas. Option values: + - `false` (default) - unknown keywords are not reported + - `true` - if an unknown keyword is present, throw an error + - `"log"` - if an unknown keyword is present, log warning +- _strictNumbers_: validate numbers strictly, failing validation for NaN and Infinity. Option values: + - `false` (default) - NaN or Infinity will pass validation for numeric types + - `true` - NaN or Infinity will not pass validation for numeric types + +##### Asynchronous validation options + +- _transpile_: Requires [ajv-async](https://github.com/ajv-validator/ajv-async) package. It determines whether Ajv transpiles compiled asynchronous validation function. Option values: + - `undefined` (default) - transpile with [nodent](https://github.com/MatAtBread/nodent) if async functions are not supported. + - `true` - always transpile with nodent. + - `false` - do not transpile; if async functions are not supported an exception will be thrown. + + +##### Advanced options + +- _meta_: add [meta-schema](http://json-schema.org/documentation.html) so it can be used by other schemas (true by default). If an object is passed, it will be used as the default meta-schema for schemas that have no `$schema` keyword. This default meta-schema MUST have `$schema` keyword. +- _validateSchema_: validate added/compiled schemas against meta-schema (true by default). `$schema` property in the schema can be http://json-schema.org/draft-07/schema or absent (draft-07 meta-schema will be used) or can be a reference to the schema previously added with `addMetaSchema` method. Option values: + - `true` (default) - if the validation fails, throw the exception. + - `"log"` - if the validation fails, log error. + - `false` - skip schema validation. +- _addUsedSchema_: by default methods `compile` and `validate` add schemas to the instance if they have `$id` (or `id`) property that doesn't start with "#". If `$id` is present and it is not unique the exception will be thrown. Set this option to `false` to skip adding schemas to the instance and the `$id` uniqueness check when these methods are used. This option does not affect `addSchema` method. +- _inlineRefs_: Affects compilation of referenced schemas. Option values: + - `true` (default) - the referenced schemas that don't have refs in them are inlined, regardless of their size - that substantially improves performance at the cost of the bigger size of compiled schema functions. + - `false` - to not inline referenced schemas (they will be compiled as separate functions). + - integer number - to limit the maximum number of keywords of the schema that will be inlined. +- _passContext_: pass validation context to custom keyword functions. If this option is `true` and you pass some context to the compiled validation function with `validate.call(context, data)`, the `context` will be available as `this` in your custom keywords. By default `this` is Ajv instance. +- _loopRequired_: by default `required` keyword is compiled into a single expression (or a sequence of statements in `allErrors` mode). In case of a very large number of properties in this keyword it may result in a very big validation function. Pass integer to set the number of properties above which `required` keyword will be validated in a loop - smaller validation function size but also worse performance. +- _ownProperties_: by default Ajv iterates over all enumerable object properties; when this option is `true` only own enumerable object properties (i.e. found directly on the object rather than on its prototype) are iterated. Contributed by @mbroadst. +- _multipleOfPrecision_: by default `multipleOf` keyword is validated by comparing the result of division with parseInt() of that result. It works for dividers that are bigger than 1. For small dividers such as 0.01 the result of the division is usually not integer (even when it should be integer, see issue [#84](https://github.com/ajv-validator/ajv/issues/84)). If you need to use fractional dividers set this option to some positive integer N to have `multipleOf` validated using this formula: `Math.abs(Math.round(division) - division) < 1e-N` (it is slower but allows for float arithmetics deviations). +- _errorDataPath_ (deprecated): set `dataPath` to point to 'object' (default) or to 'property' when validating keywords `required`, `additionalProperties` and `dependencies`. +- _messages_: Include human-readable messages in errors. `true` by default. `false` can be passed when custom messages are used (e.g. with [ajv-i18n](https://github.com/ajv-validator/ajv-i18n)). +- _sourceCode_: add `sourceCode` property to validating function (for debugging; this code can be different from the result of toString call). +- _processCode_: an optional function to process generated code before it is passed to Function constructor. It can be used to either beautify (the validating function is generated without line-breaks) or to transpile code. Starting from version 5.0.0 this option replaced options: + - `beautify` that formatted the generated function using [js-beautify](https://github.com/beautify-web/js-beautify). If you want to beautify the generated code pass a function calling `require('js-beautify').js_beautify` as `processCode: code => js_beautify(code)`. + - `transpile` that transpiled asynchronous validation function. You can still use `transpile` option with [ajv-async](https://github.com/ajv-validator/ajv-async) package. See [Asynchronous validation](#asynchronous-validation) for more information. +- _cache_: an optional instance of cache to store compiled schemas using stable-stringified schema as a key. For example, set-associative cache [sacjs](https://github.com/epoberezkin/sacjs) can be used. If not passed then a simple hash is used which is good enough for the common use case (a limited number of statically defined schemas). Cache should have methods `put(key, value)`, `get(key)`, `del(key)` and `clear()`. +- _serialize_: an optional function to serialize schema to cache key. Pass `false` to use schema itself as a key (e.g., if WeakMap used as a cache). By default [fast-json-stable-stringify](https://github.com/epoberezkin/fast-json-stable-stringify) is used. + + +## Validation errors + +In case of validation failure, Ajv assigns the array of errors to `errors` property of validation function (or to `errors` property of Ajv instance when `validate` or `validateSchema` methods were called). In case of [asynchronous validation](#asynchronous-validation), the returned promise is rejected with exception `Ajv.ValidationError` that has `errors` property. + + +### Error objects + +Each error is an object with the following properties: + +- _keyword_: validation keyword. +- _dataPath_: the path to the part of the data that was validated. By default `dataPath` uses JavaScript property access notation (e.g., `".prop[1].subProp"`). When the option `jsonPointers` is true (see [Options](#options)) `dataPath` will be set using JSON pointer standard (e.g., `"/prop/1/subProp"`). +- _schemaPath_: the path (JSON-pointer as a URI fragment) to the schema of the keyword that failed validation. +- _params_: the object with the additional information about error that can be used to create custom error messages (e.g., using [ajv-i18n](https://github.com/ajv-validator/ajv-i18n) package). See below for parameters set by all keywords. +- _message_: the standard error message (can be excluded with option `messages` set to false). +- _schema_: the schema of the keyword (added with `verbose` option). +- _parentSchema_: the schema containing the keyword (added with `verbose` option) +- _data_: the data validated by the keyword (added with `verbose` option). + +__Please note__: `propertyNames` keyword schema validation errors have an additional property `propertyName`, `dataPath` points to the object. After schema validation for each property name, if it is invalid an additional error is added with the property `keyword` equal to `"propertyNames"`. + + +### Error parameters + +Properties of `params` object in errors depend on the keyword that failed validation. + +- `maxItems`, `minItems`, `maxLength`, `minLength`, `maxProperties`, `minProperties` - property `limit` (number, the schema of the keyword). +- `additionalItems` - property `limit` (the maximum number of allowed items in case when `items` keyword is an array of schemas and `additionalItems` is false). +- `additionalProperties` - property `additionalProperty` (the property not used in `properties` and `patternProperties` keywords). +- `dependencies` - properties: + - `property` (dependent property), + - `missingProperty` (required missing dependency - only the first one is reported currently) + - `deps` (required dependencies, comma separated list as a string), + - `depsCount` (the number of required dependencies). +- `format` - property `format` (the schema of the keyword). +- `maximum`, `minimum` - properties: + - `limit` (number, the schema of the keyword), + - `exclusive` (boolean, the schema of `exclusiveMaximum` or `exclusiveMinimum`), + - `comparison` (string, comparison operation to compare the data to the limit, with the data on the left and the limit on the right; can be "<", "<=", ">", ">=") +- `multipleOf` - property `multipleOf` (the schema of the keyword) +- `pattern` - property `pattern` (the schema of the keyword) +- `required` - property `missingProperty` (required property that is missing). +- `propertyNames` - property `propertyName` (an invalid property name). +- `patternRequired` (in ajv-keywords) - property `missingPattern` (required pattern that did not match any property). +- `type` - property `type` (required type(s), a string, can be a comma-separated list) +- `uniqueItems` - properties `i` and `j` (indices of duplicate items). +- `const` - property `allowedValue` pointing to the value (the schema of the keyword). +- `enum` - property `allowedValues` pointing to the array of values (the schema of the keyword). +- `$ref` - property `ref` with the referenced schema URI. +- `oneOf` - property `passingSchemas` (array of indices of passing schemas, null if no schema passes). +- custom keywords (in case keyword definition doesn't create errors) - property `keyword` (the keyword name). + + +### Error logging + +Using the `logger` option when initiallizing Ajv will allow you to define custom logging. Here you can build upon the exisiting logging. The use of other logging packages is supported as long as the package or its associated wrapper exposes the required methods. If any of the required methods are missing an exception will be thrown. +- **Required Methods**: `log`, `warn`, `error` + +```javascript +var otherLogger = new OtherLogger(); +var ajv = new Ajv({ + logger: { + log: console.log.bind(console), + warn: function warn() { + otherLogger.logWarn.apply(otherLogger, arguments); + }, + error: function error() { + otherLogger.logError.apply(otherLogger, arguments); + console.error.apply(console, arguments); + } + } +}); +``` + + +## Plugins + +Ajv can be extended with plugins that add custom keywords, formats or functions to process generated code. When such plugin is published as npm package it is recommended that it follows these conventions: + +- it exports a function +- this function accepts ajv instance as the first parameter and returns the same instance to allow chaining +- this function can accept an optional configuration as the second parameter + +If you have published a useful plugin please submit a PR to add it to the next section. + + +## Related packages + +- [ajv-async](https://github.com/ajv-validator/ajv-async) - plugin to configure async validation mode +- [ajv-bsontype](https://github.com/BoLaMN/ajv-bsontype) - plugin to validate mongodb's bsonType formats +- [ajv-cli](https://github.com/jessedc/ajv-cli) - command line interface +- [ajv-errors](https://github.com/ajv-validator/ajv-errors) - plugin for custom error messages +- [ajv-i18n](https://github.com/ajv-validator/ajv-i18n) - internationalised error messages +- [ajv-istanbul](https://github.com/ajv-validator/ajv-istanbul) - plugin to instrument generated validation code to measure test coverage of your schemas +- [ajv-keywords](https://github.com/ajv-validator/ajv-keywords) - plugin with custom validation keywords (select, typeof, etc.) +- [ajv-merge-patch](https://github.com/ajv-validator/ajv-merge-patch) - plugin with keywords $merge and $patch +- [ajv-pack](https://github.com/ajv-validator/ajv-pack) - produces a compact module exporting validation functions +- [ajv-formats-draft2019](https://github.com/luzlab/ajv-formats-draft2019) - format validators for draft2019 that aren't already included in ajv (ie. `idn-hostname`, `idn-email`, `iri`, `iri-reference` and `duration`). + +## Some packages using Ajv + +- [webpack](https://github.com/webpack/webpack) - a module bundler. Its main purpose is to bundle JavaScript files for usage in a browser +- [jsonscript-js](https://github.com/JSONScript/jsonscript-js) - the interpreter for [JSONScript](http://www.jsonscript.org) - scripted processing of existing endpoints and services +- [osprey-method-handler](https://github.com/mulesoft-labs/osprey-method-handler) - Express middleware for validating requests and responses based on a RAML method object, used in [osprey](https://github.com/mulesoft/osprey) - validating API proxy generated from a RAML definition +- [har-validator](https://github.com/ahmadnassri/har-validator) - HTTP Archive (HAR) validator +- [jsoneditor](https://github.com/josdejong/jsoneditor) - a web-based tool to view, edit, format, and validate JSON http://jsoneditoronline.org +- [JSON Schema Lint](https://github.com/nickcmaynard/jsonschemalint) - a web tool to validate JSON/YAML document against a single JSON Schema http://jsonschemalint.com +- [objection](https://github.com/vincit/objection.js) - SQL-friendly ORM for Node.js +- [table](https://github.com/gajus/table) - formats data into a string table +- [ripple-lib](https://github.com/ripple/ripple-lib) - a JavaScript API for interacting with [Ripple](https://ripple.com) in Node.js and the browser +- [restbase](https://github.com/wikimedia/restbase) - distributed storage with REST API & dispatcher for backend services built to provide a low-latency & high-throughput API for Wikipedia / Wikimedia content +- [hippie-swagger](https://github.com/CacheControl/hippie-swagger) - [Hippie](https://github.com/vesln/hippie) wrapper that provides end to end API testing with swagger validation +- [react-form-controlled](https://github.com/seeden/react-form-controlled) - React controlled form components with validation +- [rabbitmq-schema](https://github.com/tjmehta/rabbitmq-schema) - a schema definition module for RabbitMQ graphs and messages +- [@query/schema](https://www.npmjs.com/package/@query/schema) - stream filtering with a URI-safe query syntax parsing to JSON Schema +- [chai-ajv-json-schema](https://github.com/peon374/chai-ajv-json-schema) - chai plugin to us JSON Schema with expect in mocha tests +- [grunt-jsonschema-ajv](https://github.com/SignpostMarv/grunt-jsonschema-ajv) - Grunt plugin for validating files against JSON Schema +- [extract-text-webpack-plugin](https://github.com/webpack-contrib/extract-text-webpack-plugin) - extract text from bundle into a file +- [electron-builder](https://github.com/electron-userland/electron-builder) - a solution to package and build a ready for distribution Electron app +- [addons-linter](https://github.com/mozilla/addons-linter) - Mozilla Add-ons Linter +- [gh-pages-generator](https://github.com/epoberezkin/gh-pages-generator) - multi-page site generator converting markdown files to GitHub pages +- [ESLint](https://github.com/eslint/eslint) - the pluggable linting utility for JavaScript and JSX + + +## Tests + +``` +npm install +git submodule update --init +npm test +``` + +## Contributing + +All validation functions are generated using doT templates in [dot](https://github.com/ajv-validator/ajv/tree/master/lib/dot) folder. Templates are precompiled so doT is not a run-time dependency. + +`npm run build` - compiles templates to [dotjs](https://github.com/ajv-validator/ajv/tree/master/lib/dotjs) folder. + +`npm run watch` - automatically compiles templates when files in dot folder change + +Please see [Contributing guidelines](https://github.com/ajv-validator/ajv/blob/master/CONTRIBUTING.md) + + +## Changes history + +See https://github.com/ajv-validator/ajv/releases + +__Please note__: [Changes in version 7.0.0-beta](https://github.com/ajv-validator/ajv/releases/tag/v7.0.0-beta.0) + +[Version 6.0.0](https://github.com/ajv-validator/ajv/releases/tag/v6.0.0). + +## Code of conduct + +Please review and follow the [Code of conduct](https://github.com/ajv-validator/ajv/blob/master/CODE_OF_CONDUCT.md). + +Please report any unacceptable behaviour to ajv.validator@gmail.com - it will be reviewed by the project team. + + +## Open-source software support + +Ajv is a part of [Tidelift subscription](https://tidelift.com/subscription/pkg/npm-ajv?utm_source=npm-ajv&utm_medium=referral&utm_campaign=readme) - it provides a centralised support to open-source software users, in addition to the support provided by software maintainers. + + +## License + +[MIT](https://github.com/ajv-validator/ajv/blob/master/LICENSE) diff --git "a/\344\275\231\344\277\212\347\207\225/7.1\344\275\234\344\270\232/app/node_modules/ajv/dist/ajv.bundle.js" "b/\344\275\231\344\277\212\347\207\225/7.1\344\275\234\344\270\232/app/node_modules/ajv/dist/ajv.bundle.js" new file mode 100644 index 0000000000000000000000000000000000000000..e4d9d156ff7578154a2052cf6ad00f972be63885 --- /dev/null +++ "b/\344\275\231\344\277\212\347\207\225/7.1\344\275\234\344\270\232/app/node_modules/ajv/dist/ajv.bundle.js" @@ -0,0 +1,7189 @@ +(function(f){if(typeof exports==="object"&&typeof module!=="undefined"){module.exports=f()}else if(typeof define==="function"&&define.amd){define([],f)}else{var g;if(typeof window!=="undefined"){g=window}else if(typeof global!=="undefined"){g=global}else if(typeof self!=="undefined"){g=self}else{g=this}g.Ajv = f()}})(function(){var define,module,exports;return (function(){function r(e,n,t){function o(i,f){if(!n[i]){if(!e[i]){var c="function"==typeof require&&require;if(!f&&c)return c(i,!0);if(u)return u(i,!0);var a=new Error("Cannot find module '"+i+"'");throw a.code="MODULE_NOT_FOUND",a}var p=n[i]={exports:{}};e[i][0].call(p.exports,function(r){var n=e[i][1][r];return o(n||r)},p,p.exports,r,e,n,t)}return n[i].exports}for(var u="function"==typeof require&&require,i=0;i