From 075466de14f292771b242d7172c2032647c840f6 Mon Sep 17 00:00:00 2001 From: John-David Dalton Date: Fri, 9 Nov 2012 08:41:35 -0800 Subject: [PATCH] Add Lo-Dash v0.9.2. --- ajax/libs/lodash.js/0.9.2/lodash.js | 4258 +++++++++++++++++ ajax/libs/lodash.js/0.9.2/lodash.min.js | 40 + .../lodash.js/0.9.2/lodash.underscore.min.js | 31 + ajax/libs/lodash.js/package.json | 2 +- 4 files changed, 4330 insertions(+), 1 deletion(-) create mode 100644 ajax/libs/lodash.js/0.9.2/lodash.js create mode 100644 ajax/libs/lodash.js/0.9.2/lodash.min.js create mode 100644 ajax/libs/lodash.js/0.9.2/lodash.underscore.min.js diff --git a/ajax/libs/lodash.js/0.9.2/lodash.js b/ajax/libs/lodash.js/0.9.2/lodash.js new file mode 100644 index 00000000000000..9eae931c273171 --- /dev/null +++ b/ajax/libs/lodash.js/0.9.2/lodash.js @@ -0,0 +1,4258 @@ +/*! + * Lo-Dash v0.9.2 + * (c) 2012 John-David Dalton + * Based on Underscore.js 1.4.2 + * (c) 2009-2012 Jeremy Ashkenas, DocumentCloud Inc. + * Available under MIT license + */ +;(function(window, undefined) { + + /** Detect free variable `exports` */ + var freeExports = typeof exports == 'object' && exports; + + /** Detect free variable `global` and use it as `window` */ + var freeGlobal = typeof global == 'object' && global; + if (freeGlobal.global === freeGlobal) { + window = freeGlobal; + } + + /** Used for array and object method references */ + var arrayRef = [], + // avoid a Closure Compiler bug by creatively creating an object + objectRef = new function(){}; + + /** Used to generate unique IDs */ + var idCounter = 0; + + /** Used internally to indicate various things */ + var indicatorObject = objectRef; + + /** Used by `cachedContains` as the default size when optimizations are enabled for large arrays */ + var largeArraySize = 30; + + /** Used to restore the original `_` reference in `noConflict` */ + var oldDash = window._; + + /** Used to detect template delimiter values that require a with-statement */ + var reComplexDelimiter = /[-?+=!~*%&^<>|{(\/]|\[\D|\b(?:delete|in|instanceof|new|typeof|void)\b/; + + /** Used to match HTML entities */ + var reEscapedHtml = /&(?:amp|lt|gt|quot|#x27);/g; + + /** Used to match empty string literals in compiled template source */ + var reEmptyStringLeading = /\b__p \+= '';/g, + reEmptyStringMiddle = /\b(__p \+=) '' \+/g, + reEmptyStringTrailing = /(__e\(.*?\)|\b__t\)) \+\n'';/g; + + /** Used to match regexp flags from their coerced string values */ + var reFlags = /\w*$/; + + /** Used to insert the data object variable into compiled template source */ + var reInsertVariable = /(?:__e|__t = )\(\s*(?![\d\s"']|this\.)/g; + + /** Used to detect if a method is native */ + var reNative = RegExp('^' + + (objectRef.valueOf + '') + .replace(/[.*+?^=!:${}()|[\]\/\\]/g, '\\$&') + .replace(/valueOf|for [^\]]+/g, '.+?') + '$' + ); + + /** + * Used to match ES6 template delimiters + * http://people.mozilla.org/~jorendorff/es6-draft.html#sec-7.8.6 + */ + var reEsTemplate = /\$\{((?:(?=\\?)\\?[\s\S])*?)}/g; + + /** Used to match "interpolate" template delimiters */ + var reInterpolate = /<%=([\s\S]+?)%>/g; + + /** Used to ensure capturing order of template delimiters */ + var reNoMatch = /($^)/; + + /** Used to match HTML characters */ + var reUnescapedHtml = /[&<>"']/g; + + /** Used to match unescaped characters in compiled string literals */ + var reUnescapedString = /['\n\r\t\u2028\u2029\\]/g; + + /** Used to fix the JScript [[DontEnum]] bug */ + var shadowed = [ + 'constructor', 'hasOwnProperty', 'isPrototypeOf', 'propertyIsEnumerable', + 'toLocaleString', 'toString', 'valueOf' + ]; + + /** Used to make template sourceURLs easier to identify */ + var templateCounter = 0; + + /** Native method shortcuts */ + var ceil = Math.ceil, + concat = arrayRef.concat, + floor = Math.floor, + getPrototypeOf = reNative.test(getPrototypeOf = Object.getPrototypeOf) && getPrototypeOf, + hasOwnProperty = objectRef.hasOwnProperty, + push = arrayRef.push, + propertyIsEnumerable = objectRef.propertyIsEnumerable, + slice = arrayRef.slice, + toString = objectRef.toString; + + /* Native method shortcuts for methods with the same name as other `lodash` methods */ + var nativeBind = reNative.test(nativeBind = slice.bind) && nativeBind, + nativeIsArray = reNative.test(nativeIsArray = Array.isArray) && nativeIsArray, + nativeIsFinite = window.isFinite, + nativeIsNaN = window.isNaN, + nativeKeys = reNative.test(nativeKeys = Object.keys) && nativeKeys, + nativeMax = Math.max, + nativeMin = Math.min, + nativeRandom = Math.random; + + /** `Object#toString` result shortcuts */ + var argsClass = '[object Arguments]', + arrayClass = '[object Array]', + boolClass = '[object Boolean]', + dateClass = '[object Date]', + funcClass = '[object Function]', + numberClass = '[object Number]', + objectClass = '[object Object]', + regexpClass = '[object RegExp]', + stringClass = '[object String]'; + + /** + * Detect the JScript [[DontEnum]] bug: + * + * In IE < 9 an objects own properties, shadowing non-enumerable ones, are + * made non-enumerable as well. + */ + var hasDontEnumBug; + + /** Detect if own properties are iterated after inherited properties (IE < 9) */ + var iteratesOwnLast; + + /** + * Detect if `Array#shift` and `Array#splice` augment array-like objects + * incorrectly: + * + * Firefox < 10, IE compatibility mode, and IE < 9 have buggy Array `shift()` + * and `splice()` functions that fail to remove the last element, `value[0]`, + * of array-like objects even though the `length` property is set to `0`. + * The `shift()` method is buggy in IE 8 compatibility mode, while `splice()` + * is buggy regardless of mode in IE < 9 and buggy in compatibility mode in IE 9. + */ + var hasObjectSpliceBug = (hasObjectSpliceBug = { '0': 1, 'length': 1 }, + arrayRef.splice.call(hasObjectSpliceBug, 0, 1), hasObjectSpliceBug[0]); + + /** Detect if an `arguments` object's indexes are non-enumerable (IE < 9) */ + var noArgsEnum = true; + + (function() { + var props = []; + function ctor() { this.x = 1; } + ctor.prototype = { 'valueOf': 1, 'y': 1 }; + for (var prop in new ctor) { props.push(prop); } + for (prop in arguments) { noArgsEnum = !prop; } + + hasDontEnumBug = !/valueOf/.test(props); + iteratesOwnLast = props[0] != 'x'; + }(1)); + + /** Detect if an `arguments` object's [[Class]] is unresolvable (Firefox < 4, IE < 9) */ + var noArgsClass = !isArguments(arguments); + + /** Detect if `Array#slice` cannot be used to convert strings to arrays (Opera < 10.52) */ + var noArraySliceOnStrings = slice.call('x')[0] != 'x'; + + /** + * Detect lack of support for accessing string characters by index: + * + * IE < 8 can't access characters by index and IE 8 can only access + * characters by index on string literals. + */ + var noCharByIndex = ('x'[0] + Object('x')[0]) != 'xx'; + + /** + * Detect if a node's [[Class]] is unresolvable (IE < 9) + * and that the JS engine won't error when attempting to coerce an object to + * a string without a `toString` property value of `typeof` "function". + */ + try { + var noNodeClass = ({ 'toString': 0 } + '', toString.call(window.document || 0) == objectClass); + } catch(e) { } + + /* Detect if `Function#bind` exists and is inferred to be fast (all but V8) */ + var isBindFast = nativeBind && /\n|Opera/.test(nativeBind + toString.call(window.opera)); + + /* Detect if `Object.keys` exists and is inferred to be fast (IE, Opera, V8) */ + var isKeysFast = nativeKeys && /^.+$|true/.test(nativeKeys + !!window.attachEvent); + + /** + * Detect if sourceURL syntax is usable without erroring: + * + * The JS engine in Adobe products, like InDesign, will throw a syntax error + * when it encounters a single line comment beginning with the `@` symbol. + * + * The JS engine in Narwhal will generate the function `function anonymous(){//}` + * and throw a syntax error. + * + * Avoid comments beginning `@` symbols in IE because they are part of its + * non-standard conditional compilation support. + * http://msdn.microsoft.com/en-us/library/121hztk3(v=vs.94).aspx + */ + try { + var useSourceURL = (Function('//@')(), !window.attachEvent); + } catch(e) { } + + /** Used to identify object classifications that `_.clone` supports */ + var cloneableClasses = {}; + cloneableClasses[argsClass] = cloneableClasses[funcClass] = false; + cloneableClasses[arrayClass] = cloneableClasses[boolClass] = cloneableClasses[dateClass] = + cloneableClasses[numberClass] = cloneableClasses[objectClass] = cloneableClasses[regexpClass] = + cloneableClasses[stringClass] = true; + + /** Used to determine if values are of the language type Object */ + var objectTypes = { + 'boolean': false, + 'function': true, + 'object': true, + 'number': false, + 'string': false, + 'undefined': false + }; + + /** Used to escape characters for inclusion in compiled string literals */ + var stringEscapes = { + '\\': '\\', + "'": "'", + '\n': 'n', + '\r': 'r', + '\t': 't', + '\u2028': 'u2028', + '\u2029': 'u2029' + }; + + /*--------------------------------------------------------------------------*/ + + /** + * The `lodash` function. + * + * @name _ + * @constructor + * @category Chaining + * @param {Mixed} value The value to wrap in a `lodash` instance. + * @returns {Object} Returns a `lodash` instance. + */ + function lodash(value) { + // exit early if already wrapped + if (value && value.__wrapped__) { + return value; + } + // allow invoking `lodash` without the `new` operator + if (!(this instanceof lodash)) { + return new lodash(value); + } + this.__wrapped__ = value; + } + + /** + * By default, the template delimiters used by Lo-Dash are similar to those in + * embedded Ruby (ERB). Change the following template settings to use alternative + * delimiters. + * + * @static + * @memberOf _ + * @type Object + */ + lodash.templateSettings = { + + /** + * Used to detect `data` property values to be HTML-escaped. + * + * @static + * @memberOf _.templateSettings + * @type RegExp + */ + 'escape': /<%-([\s\S]+?)%>/g, + + /** + * Used to detect code to be evaluated. + * + * @static + * @memberOf _.templateSettings + * @type RegExp + */ + 'evaluate': /<%([\s\S]+?)%>/g, + + /** + * Used to detect `data` property values to inject. + * + * @static + * @memberOf _.templateSettings + * @type RegExp + */ + 'interpolate': reInterpolate, + + /** + * Used to reference the data object in the template text. + * + * @static + * @memberOf _.templateSettings + * @type String + */ + 'variable': '' + }; + + /*--------------------------------------------------------------------------*/ + + /** + * The template used to create iterator functions. + * + * @private + * @param {Obect} data The data object used to populate the text. + * @returns {String} Returns the interpolated text. + */ + var iteratorTemplate = template( + // conditional strict mode + '<% if (obj.useStrict) { %>\'use strict\';\n<% } %>' + + + // the `iteratee` may be reassigned by the `top` snippet + 'var index, value, iteratee = <%= firstArg %>, ' + + // assign the `result` variable an initial value + 'result = <%= firstArg %>;\n' + + // exit early if the first argument is falsey + 'if (!<%= firstArg %>) return result;\n' + + // add code before the iteration branches + '<%= top %>;\n' + + + // array-like iteration: + '<% if (arrayLoop) { %>' + + 'var length = iteratee.length; index = -1;\n' + + 'if (typeof length == \'number\') {' + + + // add support for accessing string characters by index if needed + ' <% if (noCharByIndex) { %>\n' + + ' if (isString(iteratee)) {\n' + + ' iteratee = iteratee.split(\'\')\n' + + ' }' + + ' <% } %>\n' + + + // iterate over the array-like value + ' while (++index < length) {\n' + + ' value = iteratee[index];\n' + + ' <%= arrayLoop %>\n' + + ' }\n' + + '}\n' + + 'else {' + + + // object iteration: + // add support for iterating over `arguments` objects if needed + ' <% } else if (noArgsEnum) { %>\n' + + ' var length = iteratee.length; index = -1;\n' + + ' if (length && isArguments(iteratee)) {\n' + + ' while (++index < length) {\n' + + ' value = iteratee[index += \'\'];\n' + + ' <%= objectLoop %>\n' + + ' }\n' + + ' } else {' + + ' <% } %>' + + + // Firefox < 3.6, Opera > 9.50 - Opera < 11.60, and Safari < 5.1 + // (if the prototype or a property on the prototype has been set) + // incorrectly sets a function's `prototype` property [[Enumerable]] + // value to `true`. Because of this Lo-Dash standardizes on skipping + // the the `prototype` property of functions regardless of its + // [[Enumerable]] value. + ' <% if (!hasDontEnumBug) { %>\n' + + ' var skipProto = typeof iteratee == \'function\' && \n' + + ' propertyIsEnumerable.call(iteratee, \'prototype\');\n' + + ' <% } %>' + + + // iterate own properties using `Object.keys` if it's fast + ' <% if (isKeysFast && useHas) { %>\n' + + ' var ownIndex = -1,\n' + + ' ownProps = objectTypes[typeof iteratee] ? nativeKeys(iteratee) : [],\n' + + ' length = ownProps.length;\n\n' + + ' while (++ownIndex < length) {\n' + + ' index = ownProps[ownIndex];\n' + + ' <% if (!hasDontEnumBug) { %>if (!(skipProto && index == \'prototype\')) {\n <% } %>' + + ' value = iteratee[index];\n' + + ' <%= objectLoop %>\n' + + ' <% if (!hasDontEnumBug) { %>}\n<% } %>' + + ' }' + + + // else using a for-in loop + ' <% } else { %>\n' + + ' for (index in iteratee) {<%' + + ' if (!hasDontEnumBug || useHas) { %>\n if (<%' + + ' if (!hasDontEnumBug) { %>!(skipProto && index == \'prototype\')<% }' + + ' if (!hasDontEnumBug && useHas) { %> && <% }' + + ' if (useHas) { %>hasOwnProperty.call(iteratee, index)<% }' + + ' %>) {' + + ' <% } %>\n' + + ' value = iteratee[index];\n' + + ' <%= objectLoop %>;' + + ' <% if (!hasDontEnumBug || useHas) { %>\n }<% } %>\n' + + ' }' + + ' <% } %>' + + + // Because IE < 9 can't set the `[[Enumerable]]` attribute of an + // existing property and the `constructor` property of a prototype + // defaults to non-enumerable, Lo-Dash skips the `constructor` + // property when it infers it's iterating over a `prototype` object. + ' <% if (hasDontEnumBug) { %>\n\n' + + ' var ctor = iteratee.constructor;\n' + + ' <% for (var k = 0; k < 7; k++) { %>\n' + + ' index = \'<%= shadowed[k] %>\';\n' + + ' if (<%' + + ' if (shadowed[k] == \'constructor\') {' + + ' %>!(ctor && ctor.prototype === iteratee) && <%' + + ' } %>hasOwnProperty.call(iteratee, index)) {\n' + + ' value = iteratee[index];\n' + + ' <%= objectLoop %>\n' + + ' }' + + ' <% } %>' + + ' <% } %>' + + ' <% if (arrayLoop || noArgsEnum) { %>\n}<% } %>\n' + + + // add code to the bottom of the iteration function + '<%= bottom %>;\n' + + // finally, return the `result` + 'return result' + ); + + /** + * Reusable iterator options shared by `forEach`, `forIn`, and `forOwn`. + */ + var forEachIteratorOptions = { + 'args': 'collection, callback, thisArg', + 'top': 'callback = createCallback(callback, thisArg)', + 'arrayLoop': 'if (callback(value, index, collection) === false) return result', + 'objectLoop': 'if (callback(value, index, collection) === false) return result' + }; + + /** Reusable iterator options for `defaults`, and `extend` */ + var extendIteratorOptions = { + 'useHas': false, + 'args': 'object', + 'top': + 'for (var argsIndex = 1, argsLength = arguments.length; argsIndex < argsLength; argsIndex++) {\n' + + ' if (iteratee = arguments[argsIndex]) {', + 'objectLoop': 'result[index] = value', + 'bottom': ' }\n}' + }; + + /** Reusable iterator options for `forIn` and `forOwn` */ + var forOwnIteratorOptions = { + 'arrayLoop': null + }; + + /*--------------------------------------------------------------------------*/ + + /** + * Creates a function optimized to search large arrays for a given `value`, + * starting at `fromIndex`, using strict equality for comparisons, i.e. `===`. + * + * @private + * @param {Array} array The array to search. + * @param {Mixed} value The value to search for. + * @param {Number} [fromIndex=0] The index to search from. + * @param {Number} [largeSize=30] The length at which an array is considered large. + * @returns {Boolean} Returns `true` if `value` is found, else `false`. + */ + function cachedContains(array, fromIndex, largeSize) { + fromIndex || (fromIndex = 0); + + var length = array.length, + isLarge = (length - fromIndex) >= (largeSize || largeArraySize); + + if (isLarge) { + var cache = {}, + index = fromIndex - 1; + + while (++index < length) { + // manually coerce `value` to a string because `hasOwnProperty`, in some + // older versions of Firefox, coerces objects incorrectly + var key = array[index] + ''; + (hasOwnProperty.call(cache, key) ? cache[key] : (cache[key] = [])).push(array[index]); + } + } + return function(value) { + if (isLarge) { + var key = value + ''; + return hasOwnProperty.call(cache, key) && indexOf(cache[key], value) > -1; + } + return indexOf(array, value, fromIndex) > -1; + } + } + + /** + * Used by `_.max` and `_.min` as the default `callback` when a given + * `collection` is a string value. + * + * @private + * @param {String} value The character to inspect. + * @returns {Number} Returns the code unit of given character. + */ + function charAtCallback(value) { + return value.charCodeAt(0); + } + + /** + * Used by `sortBy` to compare transformed `collection` values, stable sorting + * them in ascending order. + * + * @private + * @param {Object} a The object to compare to `b`. + * @param {Object} b The object to compare to `a`. + * @returns {Number} Returns the sort order indicator of `1` or `-1`. + */ + function compareAscending(a, b) { + var ai = a.index, + bi = b.index; + + a = a.criteria; + b = b.criteria; + + // ensure a stable sort in V8 and other engines + // http://code.google.com/p/v8/issues/detail?id=90 + if (a !== b) { + if (a > b || a === undefined) { + return 1; + } + if (a < b || b === undefined) { + return -1; + } + } + return ai < bi ? -1 : 1; + } + + /** + * Creates a function that, when called, invokes `func` with the `this` + * binding of `thisArg` and prepends any `partailArgs` to the arguments passed + * to the bound function. + * + * @private + * @param {Function|String} func The function to bind or the method name. + * @param {Mixed} [thisArg] The `this` binding of `func`. + * @param {Array} partialArgs An array of arguments to be partially applied. + * @returns {Function} Returns the new bound function. + */ + function createBound(func, thisArg, partialArgs) { + var isFunc = isFunction(func), + isPartial = !partialArgs, + methodName = func; + + // juggle arguments + if (isPartial) { + partialArgs = thisArg; + } + + function bound() { + // `Function#bind` spec + // http://es5.github.com/#x15.3.4.5 + var args = arguments, + thisBinding = isPartial ? this : thisArg; + + if (!isFunc) { + func = thisArg[methodName]; + } + if (partialArgs.length) { + args = args.length + ? partialArgs.concat(slice.call(args)) + : partialArgs; + } + if (this instanceof bound) { + // get `func` instance if `bound` is invoked in a `new` expression + noop.prototype = func.prototype; + thisBinding = new noop; + + // mimic the constructor's `return` behavior + // http://es5.github.com/#x13.2.2 + var result = func.apply(thisBinding, args); + return isObject(result) + ? result + : thisBinding + } + return func.apply(thisBinding, args); + } + return bound; + } + + /** + * Produces an iteration callback bound to an optional `thisArg`. If `func` is + * a property name, the callback will return the property value for a given element. + * + * @private + * @param {Function|String} [func=identity|property] The function called per + * iteration or property name to query. + * @param {Mixed} [thisArg] The `this` binding of `callback`. + * @returns {Function} Returns a callback function. + */ + function createCallback(func, thisArg) { + if (!func) { + return identity; + } + if (typeof func != 'function') { + return function(object) { + return object[func]; + }; + } + if (thisArg !== undefined) { + return function(value, index, object) { + return func.call(thisArg, value, index, object); + }; + } + return func; + } + + /** + * Creates compiled iteration functions. + * + * @private + * @param {Object} [options1, options2, ...] The compile options object(s). + * useHas - A boolean to specify using `hasOwnProperty` checks in the object loop. + * args - A string of comma separated arguments the iteration function will accept. + * top - A string of code to execute before the iteration branches. + * arrayLoop - A string of code to execute in the array loop. + * objectLoop - A string of code to execute in the object loop. + * bottom - A string of code to execute after the iteration branches. + * + * @returns {Function} Returns the compiled function. + */ + function createIterator() { + var data = { + 'arrayLoop': '', + 'bottom': '', + 'hasDontEnumBug': hasDontEnumBug, + 'isKeysFast': isKeysFast, + 'objectLoop': '', + 'noArgsEnum': noArgsEnum, + 'noCharByIndex': noCharByIndex, + 'shadowed': shadowed, + 'top': '', + 'useHas': true + }; + + // merge options into a template data object + for (var object, index = 0; object = arguments[index]; index++) { + for (var key in object) { + data[key] = object[key]; + } + } + var args = data.args; + data.firstArg = /^[^,]+/.exec(args)[0]; + + // create the function factory + var factory = Function( + 'createCallback, hasOwnProperty, isArguments, isString, objectTypes, ' + + 'nativeKeys, propertyIsEnumerable', + 'return function(' + args + ') {\n' + iteratorTemplate(data) + '\n}' + ); + // return the compiled function + return factory( + createCallback, hasOwnProperty, isArguments, isString, objectTypes, + nativeKeys, propertyIsEnumerable + ); + } + + /** + * Used by `template` to escape characters for inclusion in compiled + * string literals. + * + * @private + * @param {String} match The matched character to escape. + * @returns {String} Returns the escaped character. + */ + function escapeStringChar(match) { + return '\\' + stringEscapes[match]; + } + + /** + * Used by `escape` to convert characters to HTML entities. + * + * @private + * @param {String} match The matched character to escape. + * @returns {String} Returns the escaped character. + */ + function escapeHtmlChar(match) { + return htmlEscapes[match]; + } + + /** + * A no-operation function. + * + * @private + */ + function noop() { + // no operation performed + } + + /** + * Used by `unescape` to convert HTML entities to characters. + * + * @private + * @param {String} match The matched character to unescape. + * @returns {String} Returns the unescaped character. + */ + function unescapeHtmlChar(match) { + return htmlUnescapes[match]; + } + + /*--------------------------------------------------------------------------*/ + + /** + * Checks if `value` is an `arguments` object. + * + * @static + * @memberOf _ + * @category Objects + * @param {Mixed} value The value to check. + * @returns {Boolean} Returns `true` if the `value` is an `arguments` object, else `false`. + * @example + * + * (function() { return _.isArguments(arguments); })(1, 2, 3); + * // => true + * + * _.isArguments([1, 2, 3]); + * // => false + */ + function isArguments(value) { + return toString.call(value) == argsClass; + } + // fallback for browsers that can't detect `arguments` objects by [[Class]] + if (noArgsClass) { + isArguments = function(value) { + return value ? hasOwnProperty.call(value, 'callee') : false; + }; + } + + /** + * Iterates over `object`'s own and inherited enumerable properties, executing + * the `callback` for each property. The `callback` is bound to `thisArg` and + * invoked with three arguments; (value, key, object). Callbacks may exit iteration + * early by explicitly returning `false`. + * + * @static + * @memberOf _ + * @category Objects + * @param {Object} object The object to iterate over. + * @param {Function} callback The function called per iteration. + * @param {Mixed} [thisArg] The `this` binding of `callback`. + * @returns {Object} Returns `object`. + * @example + * + * function Dog(name) { + * this.name = name; + * } + * + * Dog.prototype.bark = function() { + * alert('Woof, woof!'); + * }; + * + * _.forIn(new Dog('Dagny'), function(value, key) { + * alert(key); + * }); + * // => alerts 'name' and 'bark' (order is not guaranteed) + */ + var forIn = createIterator(forEachIteratorOptions, forOwnIteratorOptions, { + 'useHas': false + }); + + /** + * Iterates over `object`'s own enumerable properties, executing the `callback` + * for each property. The `callback` is bound to `thisArg` and invoked with three + * arguments; (value, key, object). Callbacks may exit iteration early by explicitly + * returning `false`. + * + * @static + * @memberOf _ + * @category Objects + * @param {Object} object The object to iterate over. + * @param {Function} callback The function called per iteration. + * @param {Mixed} [thisArg] The `this` binding of `callback`. + * @returns {Object} Returns `object`. + * @example + * + * _.forOwn({ '0': 'zero', '1': 'one', 'length': 2 }, function(num, key) { + * alert(key); + * }); + * // => alerts '0', '1', and 'length' (order is not guaranteed) + */ + var forOwn = createIterator(forEachIteratorOptions, forOwnIteratorOptions); + + /** + * A fallback implementation of `isPlainObject` that checks if a given `value` + * is an object created by the `Object` constructor, assuming objects created + * by the `Object` constructor have no inherited enumerable properties and that + * there are no `Object.prototype` extensions. + * + * @private + * @param {Mixed} value The value to check. + * @returns {Boolean} Returns `true` if `value` is a plain object, else `false`. + */ + function shimIsPlainObject(value) { + // avoid non-objects and false positives for `arguments` objects + var result = false; + if (!(value && typeof value == 'object') || isArguments(value)) { + return result; + } + // IE < 9 presents DOM nodes as `Object` objects except they have `toString` + // methods that are `typeof` "string" and still can coerce nodes to strings. + // Also check that the constructor is `Object` (i.e. `Object instanceof Object`) + var ctor = value.constructor; + if ((!noNodeClass || !(typeof value.toString != 'function' && typeof (value + '') == 'string')) && + (!isFunction(ctor) || ctor instanceof ctor)) { + // IE < 9 iterates inherited properties before own properties. If the first + // iterated property is an object's own property then there are no inherited + // enumerable properties. + if (iteratesOwnLast) { + forIn(value, function(value, key, object) { + result = !hasOwnProperty.call(object, key); + return false; + }); + return result === false; + } + // In most environments an object's own properties are iterated before + // its inherited properties. If the last iterated property is an object's + // own property then there are no inherited enumerable properties. + forIn(value, function(value, key) { + result = key; + }); + return result === false || hasOwnProperty.call(value, result); + } + return result; + } + + /** + * A fallback implementation of `Object.keys` that produces an array of the + * given object's own enumerable property names. + * + * @private + * @param {Object} object The object to inspect. + * @returns {Array} Returns a new array of property names. + */ + function shimKeys(object) { + var result = []; + forOwn(object, function(value, key) { + result.push(key); + }); + return result; + } + + /** + * Used to convert characters to HTML entities: + * + * Though the `>` character is escaped for symmetry, characters like `>` and `/` + * don't require escaping in HTML and have no special meaning unless they're part + * of a tag or an unquoted attribute value. + * http://mathiasbynens.be/notes/ambiguous-ampersands (under "semi-related fun fact") + */ + var htmlEscapes = { + '&': '&', + '<': '<', + '>': '>', + '"': '"', + "'": ''' + }; + + /** Used to convert HTML entities to characters */ + var htmlUnescapes = invert(htmlEscapes); + + /*--------------------------------------------------------------------------*/ + + /** + * Creates a clone of `value`. If `deep` is `true`, all nested objects will + * also be cloned otherwise they will be assigned by reference. Functions, DOM + * nodes, `arguments` objects, and objects created by constructors other than + * `Object` are **not** cloned. + * + * @static + * @memberOf _ + * @category Objects + * @param {Mixed} value The value to clone. + * @param {Boolean} deep A flag to indicate a deep clone. + * @param- {Object} [guard] Internally used to allow this method to work with + * others like `_.map` without using their callback `index` argument for `deep`. + * @param- {Array} [stackA=[]] Internally used to track traversed source objects. + * @param- {Array} [stackB=[]] Internally used to associate clones with their + * source counterparts. + * @returns {Mixed} Returns the cloned `value`. + * @example + * + * var stooges = [ + * { 'name': 'moe', 'age': 40 }, + * { 'name': 'larry', 'age': 50 }, + * { 'name': 'curly', 'age': 60 } + * ]; + * + * _.clone({ 'name': 'moe' }); + * // => { 'name': 'moe' } + * + * var shallow = _.clone(stooges); + * shallow[0] === stooges[0]; + * // => true + * + * var deep = _.clone(stooges, true); + * shallow[0] === stooges[0]; + * // => false + */ + function clone(value, deep, guard, stackA, stackB) { + if (value == null) { + return value; + } + if (guard) { + deep = false; + } + // inspect [[Class]] + var isObj = isObject(value); + if (isObj) { + // don't clone `arguments` objects, functions, or non-object Objects + var className = toString.call(value); + if (!cloneableClasses[className] || (noArgsClass && isArguments(value))) { + return value; + } + var isArr = className == arrayClass; + isObj = isArr || (className == objectClass ? isPlainObject(value) : isObj); + } + // shallow clone + if (!isObj || !deep) { + // don't clone functions + return isObj + ? (isArr ? slice.call(value) : extend({}, value)) + : value; + } + + var ctor = value.constructor; + switch (className) { + case boolClass: + case dateClass: + return new ctor(+value); + + case numberClass: + case stringClass: + return new ctor(value); + + case regexpClass: + return ctor(value.source, reFlags.exec(value)); + } + // check for circular references and return corresponding clone + stackA || (stackA = []); + stackB || (stackB = []); + + var length = stackA.length; + while (length--) { + if (stackA[length] == value) { + return stackB[length]; + } + } + // init cloned object + var result = isArr ? ctor(value.length) : {}; + + // add the source value to the stack of traversed objects + // and associate it with its clone + stackA.push(value); + stackB.push(result); + + // recursively populate clone (susceptible to call stack limits) + (isArr ? forEach : forOwn)(value, function(objValue, key) { + result[key] = clone(objValue, deep, null, stackA, stackB); + }); + + return result; + } + + /** + * Assigns enumerable properties of the default object(s) to the `destination` + * object for all `destination` properties that resolve to `null`/`undefined`. + * Once a property is set, additional defaults of the same property will be + * ignored. + * + * @static + * @memberOf _ + * @category Objects + * @param {Object} object The destination object. + * @param {Object} [default1, default2, ...] The default objects. + * @returns {Object} Returns the destination object. + * @example + * + * var iceCream = { 'flavor': 'chocolate' }; + * _.defaults(iceCream, { 'flavor': 'vanilla', 'sprinkles': 'rainbow' }); + * // => { 'flavor': 'chocolate', 'sprinkles': 'rainbow' } + */ + var defaults = createIterator(extendIteratorOptions, { + 'objectLoop': 'if (result[index] == null) ' + extendIteratorOptions.objectLoop + }); + + /** + * Assigns enumerable properties of the source object(s) to the `destination` + * object. Subsequent sources will overwrite propery assignments of previous + * sources. + * + * @static + * @memberOf _ + * @category Objects + * @param {Object} object The destination object. + * @param {Object} [source1, source2, ...] The source objects. + * @returns {Object} Returns the destination object. + * @example + * + * _.extend({ 'name': 'moe' }, { 'age': 40 }); + * // => { 'name': 'moe', 'age': 40 } + */ + var extend = createIterator(extendIteratorOptions); + + /** + * Creates a sorted array of all enumerable properties, own and inherited, + * of `object` that have function values. + * + * @static + * @memberOf _ + * @alias methods + * @category Objects + * @param {Object} object The object to inspect. + * @returns {Array} Returns a new array of property names that have function values. + * @example + * + * _.functions(_); + * // => ['all', 'any', 'bind', 'bindAll', 'clone', 'compact', 'compose', ...] + */ + function functions(object) { + var result = []; + forIn(object, function(value, key) { + if (isFunction(value)) { + result.push(key); + } + }); + return result.sort(); + } + + /** + * Checks if the specified object `property` exists and is a direct property, + * instead of an inherited property. + * + * @static + * @memberOf _ + * @category Objects + * @param {Object} object The object to check. + * @param {String} property The property to check for. + * @returns {Boolean} Returns `true` if key is a direct property, else `false`. + * @example + * + * _.has({ 'a': 1, 'b': 2, 'c': 3 }, 'b'); + * // => true + */ + function has(object, property) { + return object ? hasOwnProperty.call(object, property) : false; + } + + /** + * Creates an object composed of the inverted keys and values of the given `object`. + * + * @static + * @memberOf _ + * @category Objects + * @param {Object} object The object to invert. + * @returns {Object} Returns the created inverted object. + * @example + * + * _.invert({ 'first': 'Moe', 'second': 'Larry', 'third': 'Curly' }); + * // => { 'Moe': 'first', 'Larry': 'second', 'Curly': 'third' } (order is not guaranteed) + */ + function invert(object) { + var result = {}; + forOwn(object, function(value, key) { + result[value] = key; + }); + return result; + } + + /** + * Checks if `value` is an array. + * + * @static + * @memberOf _ + * @category Objects + * @param {Mixed} value The value to check. + * @returns {Boolean} Returns `true` if the `value` is an array, else `false`. + * @example + * + * (function() { return _.isArray(arguments); })(); + * // => false + * + * _.isArray([1, 2, 3]); + * // => true + */ + var isArray = nativeIsArray || function(value) { + return toString.call(value) == arrayClass; + }; + + /** + * Checks if `value` is a boolean (`true` or `false`) value. + * + * @static + * @memberOf _ + * @category Objects + * @param {Mixed} value The value to check. + * @returns {Boolean} Returns `true` if the `value` is a boolean value, else `false`. + * @example + * + * _.isBoolean(null); + * // => false + */ + function isBoolean(value) { + return value === true || value === false || toString.call(value) == boolClass; + } + + /** + * Checks if `value` is a date. + * + * @static + * @memberOf _ + * @category Objects + * @param {Mixed} value The value to check. + * @returns {Boolean} Returns `true` if the `value` is a date, else `false`. + * @example + * + * _.isDate(new Date); + * // => true + */ + function isDate(value) { + return toString.call(value) == dateClass; + } + + /** + * Checks if `value` is a DOM element. + * + * @static + * @memberOf _ + * @category Objects + * @param {Mixed} value The value to check. + * @returns {Boolean} Returns `true` if the `value` is a DOM element, else `false`. + * @example + * + * _.isElement(document.body); + * // => true + */ + function isElement(value) { + return value ? value.nodeType === 1 : false; + } + + /** + * Checks if `value` is empty. Arrays, strings, or `arguments` objects with a + * length of `0` and objects with no own enumerable properties are considered + * "empty". + * + * @static + * @memberOf _ + * @category Objects + * @param {Array|Object|String} value The value to inspect. + * @returns {Boolean} Returns `true` if the `value` is empty, else `false`. + * @example + * + * _.isEmpty([1, 2, 3]); + * // => false + * + * _.isEmpty({}); + * // => true + * + * _.isEmpty(''); + * // => true + */ + function isEmpty(value) { + var result = true; + if (!value) { + return result; + } + var className = toString.call(value), + length = value.length; + + if ((className == arrayClass || className == stringClass || + className == argsClass || (noArgsClass && isArguments(value))) || + (className == objectClass && typeof length == 'number' && isFunction(value.splice))) { + return !length; + } + forOwn(value, function() { + return (result = false); + }); + return result; + } + + /** + * Performs a deep comparison between two values to determine if they are + * equivalent to each other. + * + * @static + * @memberOf _ + * @category Objects + * @param {Mixed} a The value to compare. + * @param {Mixed} b The other value to compare. + * @param- {Object} [stackA=[]] Internally used track traversed `a` objects. + * @param- {Object} [stackB=[]] Internally used track traversed `b` objects. + * @returns {Boolean} Returns `true` if the values are equvalent, else `false`. + * @example + * + * var moe = { 'name': 'moe', 'luckyNumbers': [13, 27, 34] }; + * var clone = { 'name': 'moe', 'luckyNumbers': [13, 27, 34] }; + * + * moe == clone; + * // => false + * + * _.isEqual(moe, clone); + * // => true + */ + function isEqual(a, b, stackA, stackB) { + // exit early for identical values + if (a === b) { + // treat `+0` vs. `-0` as not equal + return a !== 0 || (1 / a == 1 / b); + } + // a strict comparison is necessary because `null == undefined` + if (a == null || b == null) { + return a === b; + } + // compare [[Class]] names + var className = toString.call(a); + if (className != toString.call(b)) { + return false; + } + switch (className) { + case boolClass: + case dateClass: + // coerce dates and booleans to numbers, dates to milliseconds and booleans + // to `1` or `0`, treating invalid dates coerced to `NaN` as not equal + return +a == +b; + + case numberClass: + // treat `NaN` vs. `NaN` as equal + return a != +a + ? b != +b + // but treat `+0` vs. `-0` as not equal + : (a == 0 ? (1 / a == 1 / b) : a == +b); + + case regexpClass: + case stringClass: + // coerce regexes to strings (http://es5.github.com/#x15.10.6.4) + // treat string primitives and their corresponding object instances as equal + return a == b + ''; + } + // exit early, in older browsers, if `a` is array-like but not `b` + var isArr = className == arrayClass || className == argsClass; + if (noArgsClass && !isArr && (isArr = isArguments(a)) && !isArguments(b)) { + return false; + } + if (!isArr) { + // unwrap any `lodash` wrapped values + if (a.__wrapped__ || b.__wrapped__) { + return isEqual(a.__wrapped__ || a, b.__wrapped__ || b); + } + // exit for functions and DOM nodes + if (className != objectClass || (noNodeClass && ( + (typeof a.toString != 'function' && typeof (a + '') == 'string') || + (typeof b.toString != 'function' && typeof (b + '') == 'string')))) { + return false; + } + var ctorA = a.constructor, + ctorB = b.constructor; + + // non `Object` object instances with different constructors are not equal + if (ctorA != ctorB && !( + isFunction(ctorA) && ctorA instanceof ctorA && + isFunction(ctorB) && ctorB instanceof ctorB + )) { + return false; + } + } + // assume cyclic structures are equal + // the algorithm for detecting cyclic structures is adapted from ES 5.1 + // section 15.12.3, abstract operation `JO` (http://es5.github.com/#x15.12.3) + stackA || (stackA = []); + stackB || (stackB = []); + + var length = stackA.length; + while (length--) { + if (stackA[length] == a) { + return stackB[length] == b; + } + } + + var index = -1, + result = true, + size = 0; + + // add `a` and `b` to the stack of traversed objects + stackA.push(a); + stackB.push(b); + + // recursively compare objects and arrays (susceptible to call stack limits) + if (isArr) { + // compare lengths to determine if a deep comparison is necessary + size = a.length; + result = size == b.length; + + if (result) { + // deep compare the contents, ignoring non-numeric properties + while (size--) { + if (!(result = isEqual(a[size], b[size], stackA, stackB))) { + break; + } + } + } + return result; + } + // deep compare objects + for (var key in a) { + if (hasOwnProperty.call(a, key)) { + // count the number of properties. + size++; + // deep compare each property value. + if (!(hasOwnProperty.call(b, key) && isEqual(a[key], b[key], stackA, stackB))) { + return false; + } + } + } + // ensure both objects have the same number of properties + for (key in b) { + // The JS engine in Adobe products, like InDesign, has a bug that causes + // `!size--` to throw an error so it must be wrapped in parentheses. + // https://github.com/documentcloud/underscore/issues/355 + if (hasOwnProperty.call(b, key) && !(size--)) { + // `size` will be `-1` if `b` has more properties than `a` + return false; + } + } + // handle JScript [[DontEnum]] bug + if (hasDontEnumBug) { + while (++index < 7) { + key = shadowed[index]; + if (hasOwnProperty.call(a, key) && + !(hasOwnProperty.call(b, key) && isEqual(a[key], b[key], stackA, stackB))) { + return false; + } + } + } + return true; + } + + /** + * Checks if `value` is, or can be coerced to, a finite number. + * + * Note: This is not the same as native `isFinite`, which will return true for + * booleans and empty strings. See http://es5.github.com/#x15.1.2.5. + * + * @deprecated + * @static + * @memberOf _ + * @category Objects + * @param {Mixed} value The value to check. + * @returns {Boolean} Returns `true` if the `value` is a finite number, else `false`. + * @example + * + * _.isFinite(-101); + * // => true + * + * _.isFinite('10'); + * // => true + * + * _.isFinite(true); + * // => false + * + * _.isFinite(''); + * // => false + * + * _.isFinite(Infinity); + * // => false + */ + function isFinite(value) { + return nativeIsFinite(value) && !nativeIsNaN(parseFloat(value)); + } + + /** + * Checks if `value` is a function. + * + * @static + * @memberOf _ + * @category Objects + * @param {Mixed} value The value to check. + * @returns {Boolean} Returns `true` if the `value` is a function, else `false`. + * @example + * + * _.isFunction(_); + * // => true + */ + function isFunction(value) { + return typeof value == 'function'; + } + // fallback for older versions of Chrome and Safari + if (isFunction(/x/)) { + isFunction = function(value) { + return toString.call(value) == funcClass; + }; + } + + /** + * Checks if `value` is the language type of Object. + * (e.g. arrays, functions, objects, regexes, `new Number(0)`, and `new String('')`) + * + * @static + * @memberOf _ + * @category Objects + * @param {Mixed} value The value to check. + * @returns {Boolean} Returns `true` if the `value` is an object, else `false`. + * @example + * + * _.isObject({}); + * // => true + * + * _.isObject([1, 2, 3]); + * // => true + * + * _.isObject(1); + * // => false + */ + function isObject(value) { + // check if the value is the ECMAScript language type of Object + // http://es5.github.com/#x8 + // and avoid a V8 bug + // http://code.google.com/p/v8/issues/detail?id=2291 + return value ? objectTypes[typeof value] : false; + } + + /** + * Checks if `value` is `NaN`. + * + * Note: This is not the same as native `isNaN`, which will return true for + * `undefined` and other values. See http://es5.github.com/#x15.1.2.4. + * + * @deprecated + * @static + * @memberOf _ + * @category Objects + * @param {Mixed} value The value to check. + * @returns {Boolean} Returns `true` if the `value` is `NaN`, else `false`. + * @example + * + * _.isNaN(NaN); + * // => true + * + * _.isNaN(new Number(NaN)); + * // => true + * + * isNaN(undefined); + * // => true + * + * _.isNaN(undefined); + * // => false + */ + function isNaN(value) { + // `NaN` as a primitive is the only value that is not equal to itself + // (perform the [[Class]] check first to avoid errors with some host objects in IE) + return toString.call(value) == numberClass && value != +value + } + + /** + * Checks if `value` is `null`. + * + * @deprecated + * @static + * @memberOf _ + * @category Objects + * @param {Mixed} value The value to check. + * @returns {Boolean} Returns `true` if the `value` is `null`, else `false`. + * @example + * + * _.isNull(null); + * // => true + * + * _.isNull(undefined); + * // => false + */ + function isNull(value) { + return value === null; + } + + /** + * Checks if `value` is a number. + * + * @static + * @memberOf _ + * @category Objects + * @param {Mixed} value The value to check. + * @returns {Boolean} Returns `true` if the `value` is a number, else `false`. + * @example + * + * _.isNumber(8.4 * 5); + * // => true + */ + function isNumber(value) { + return toString.call(value) == numberClass; + } + + /** + * Checks if a given `value` is an object created by the `Object` constructor. + * + * @static + * @memberOf _ + * @category Objects + * @param {Mixed} value The value to check. + * @returns {Boolean} Returns `true` if `value` is a plain object, else `false`. + * @example + * + * function Stooge(name, age) { + * this.name = name; + * this.age = age; + * } + * + * _.isPlainObject(new Stooge('moe', 40)); + * // => false + * + * _.isPlainObject([1, 2, 3]); + * // => false + * + * _.isPlainObject({ 'name': 'moe', 'age': 40 }); + * // => true + */ + var isPlainObject = !getPrototypeOf ? shimIsPlainObject : function(value) { + if (!(value && typeof value == 'object')) { + return false; + } + var valueOf = value.valueOf, + objProto = typeof valueOf == 'function' && (objProto = getPrototypeOf(valueOf)) && getPrototypeOf(objProto); + + return objProto + ? value == objProto || (getPrototypeOf(value) == objProto && !isArguments(value)) + : shimIsPlainObject(value); + }; + + /** + * Checks if `value` is a regular expression. + * + * @static + * @memberOf _ + * @category Objects + * @param {Mixed} value The value to check. + * @returns {Boolean} Returns `true` if the `value` is a regular expression, else `false`. + * @example + * + * _.isRegExp(/moe/); + * // => true + */ + function isRegExp(value) { + return toString.call(value) == regexpClass; + } + + /** + * Checks if `value` is a string. + * + * @static + * @memberOf _ + * @category Objects + * @param {Mixed} value The value to check. + * @returns {Boolean} Returns `true` if the `value` is a string, else `false`. + * @example + * + * _.isString('moe'); + * // => true + */ + function isString(value) { + return toString.call(value) == stringClass; + } + + /** + * Checks if `value` is `undefined`. + * + * @deprecated + * @static + * @memberOf _ + * @category Objects + * @param {Mixed} value The value to check. + * @returns {Boolean} Returns `true` if the `value` is `undefined`, else `false`. + * @example + * + * _.isUndefined(void 0); + * // => true + */ + function isUndefined(value) { + return value === undefined; + } + + /** + * Creates an array composed of the own enumerable property names of `object`. + * + * @static + * @memberOf _ + * @category Objects + * @param {Object} object The object to inspect. + * @returns {Array} Returns a new array of property names. + * @example + * + * _.keys({ 'one': 1, 'two': 2, 'three': 3 }); + * // => ['one', 'two', 'three'] (order is not guaranteed) + */ + var keys = !nativeKeys ? shimKeys : function(object) { + // avoid iterating over the `prototype` property + return typeof object == 'function' && propertyIsEnumerable.call(object, 'prototype') + ? shimKeys(object) + : (isObject(object) ? nativeKeys(object) : []); + }; + + /** + * Merges enumerable properties of the source object(s) into the `destination` + * object. Subsequent sources will overwrite propery assignments of previous + * sources. + * + * @static + * @memberOf _ + * @category Objects + * @param {Object} object The destination object. + * @param {Object} [source1, source2, ...] The source objects. + * @param- {Object} [indicator] Internally used to indicate that the `stack` + * argument is an array of traversed objects instead of another source object. + * @param- {Array} [stackA=[]] Internally used to track traversed source objects. + * @param- {Array} [stackB=[]] Internally used to associate values with their + * source counterparts. + * @returns {Object} Returns the destination object. + * @example + * + * var stooges = [ + * { 'name': 'moe' }, + * { 'name': 'larry' } + * ]; + * + * var ages = [ + * { 'age': 40 }, + * { 'age': 50 } + * ]; + * + * _.merge(stooges, ages); + * // => [{ 'name': 'moe', 'age': 40 }, { 'name': 'larry', 'age': 50 }] + */ + function merge(object, source, indicator) { + var args = arguments, + index = 0, + length = 2, + stackA = args[3], + stackB = args[4]; + + if (indicator !== objectRef) { + stackA = []; + stackB = []; + length = args.length; + } + while (++index < length) { + forOwn(args[index], function(source, key) { + var found, isArr, value; + if (source && ((isArr = isArray(source)) || isPlainObject(source))) { + // avoid merging previously merged cyclic sources + var stackLength = stackA.length; + while (stackLength--) { + found = stackA[stackLength] == source; + if (found) { + break; + } + } + if (found) { + object[key] = stackB[stackLength]; + } + else { + // add `source` and associated `value` to the stack of traversed objects + stackA.push(source); + stackB.push(value = (value = object[key], isArr) + ? (isArray(value) ? value : []) + : (isPlainObject(value) ? value : {}) + ); + // recursively merge objects and arrays (susceptible to call stack limits) + object[key] = merge(value, source, objectRef, stackA, stackB); + } + } else if (source != null) { + object[key] = source; + } + }); + } + return object; + } + + /** + * Creates a shallow clone of `object` excluding the specified properties. + * Property names may be specified as individual arguments or as arrays of + * property names. If `callback` is passed, it will be executed for each property + * in the `object`, omitting the properties `callback` returns truthy for. The + * `callback` is bound to `thisArg` and invoked with three arguments; (value, key, object). + * + * @static + * @memberOf _ + * @category Objects + * @param {Object} object The source object. + * @param {Function|String} callback|[prop1, prop2, ...] The properties to omit + * or the function called per iteration. + * @param {Mixed} [thisArg] The `this` binding of `callback`. + * @returns {Object} Returns an object without the omitted properties. + * @example + * + * _.omit({ 'name': 'moe', 'age': 40, 'userid': 'moe1' }, 'userid'); + * // => { 'name': 'moe', 'age': 40 } + * + * _.omit({ 'name': 'moe', '_hint': 'knucklehead', '_seed': '96c4eb' }, function(value, key) { + * return key.charAt(0) == '_'; + * }); + * // => { 'name': 'moe' } + */ + function omit(object, callback, thisArg) { + var isFunc = typeof callback == 'function', + result = {}; + + if (isFunc) { + callback = createCallback(callback, thisArg); + } else { + var props = concat.apply(arrayRef, arguments); + } + forIn(object, function(value, key, object) { + if (isFunc + ? !callback(value, key, object) + : indexOf(props, key, 1) < 0 + ) { + result[key] = value; + } + }); + return result; + } + + /** + * Creates a two dimensional array of the given object's key-value pairs, + * i.e. `[[key1, value1], [key2, value2]]`. + * + * @static + * @memberOf _ + * @category Objects + * @param {Object} object The object to inspect. + * @returns {Array} Returns new array of key-value pairs. + * @example + * + * _.pairs({ 'moe': 30, 'larry': 40, 'curly': 50 }); + * // => [['moe', 30], ['larry', 40], ['curly', 50]] (order is not guaranteed) + */ + function pairs(object) { + var result = []; + forOwn(object, function(value, key) { + result.push([key, value]); + }); + return result; + } + + /** + * Creates a shallow clone of `object` composed of the specified properties. + * Property names may be specified as individual arguments or as arrays of + * property names. If `callback` is passed, it will be executed for each property + * in the `object`, picking the properties `callback` returns truthy for. The + * `callback` is bound to `thisArg` and invoked with three arguments; (value, key, object). + * + * @static + * @memberOf _ + * @category Objects + * @param {Object} object The source object. + * @param {Function|String} callback|[prop1, prop2, ...] The properties to pick + * or the function called per iteration. + * @param {Mixed} [thisArg] The `this` binding of `callback`. + * @returns {Object} Returns an object composed of the picked properties. + * @example + * + * _.pick({ 'name': 'moe', 'age': 40, 'userid': 'moe1' }, 'name', 'age'); + * // => { 'name': 'moe', 'age': 40 } + * + * _.pick({ 'name': 'moe', '_hint': 'knucklehead', '_seed': '96c4eb' }, function(value, key) { + * return key.charAt(0) != '_'; + * }); + * // => { 'name': 'moe' } + */ + function pick(object, callback, thisArg) { + var result = {}; + if (typeof callback != 'function') { + var index = 0, + props = concat.apply(arrayRef, arguments), + length = props.length; + + while (++index < length) { + var key = props[index]; + if (key in object) { + result[key] = object[key]; + } + } + } else { + callback = createCallback(callback, thisArg); + forIn(object, function(value, key, object) { + if (callback(value, key, object)) { + result[key] = value; + } + }); + } + return result; + } + + /** + * Creates an array composed of the own enumerable property values of `object`. + * + * @static + * @memberOf _ + * @category Objects + * @param {Object} object The object to inspect. + * @returns {Array} Returns a new array of property values. + * @example + * + * _.values({ 'one': 1, 'two': 2, 'three': 3 }); + * // => [1, 2, 3] + */ + function values(object) { + var result = []; + forOwn(object, function(value) { + result.push(value); + }); + return result; + } + + /*--------------------------------------------------------------------------*/ + + /** + * Checks if a given `target` element is present in a `collection` using strict + * equality for comparisons, i.e. `===`. If `fromIndex` is negative, it is used + * as the offset from the end of the collection. + * + * @static + * @memberOf _ + * @alias include + * @category Collections + * @param {Array|Object|String} collection The collection to iterate over. + * @param {Mixed} target The value to check for. + * @param {Number} [fromIndex=0] The index to search from. + * @returns {Boolean} Returns `true` if the `target` element is found, else `false`. + * @example + * + * _.contains([1, 2, 3], 1); + * // => true + * + * _.contains([1, 2, 3], 1, 2); + * // => false + * + * _.contains({ 'name': 'moe', 'age': 40 }, 'moe'); + * // => true + * + * _.contains('curly', 'ur'); + * // => true + */ + function contains(collection, target, fromIndex) { + var index = -1, + length = collection ? collection.length : 0; + + fromIndex = (fromIndex < 0 ? nativeMax(0, length + fromIndex) : fromIndex) || 0; + if (typeof length == 'number') { + return (isString(collection) + ? collection.indexOf(target, fromIndex) + : indexOf(collection, target, fromIndex) + ) > -1; + } + return some(collection, function(value) { + return ++index >= fromIndex && value === target; + }); + } + + /** + * Creates an object composed of keys returned from running each element of + * `collection` through a `callback`. The corresponding value of each key is + * the number of times the key was returned by `callback`. The `callback` is + * bound to `thisArg` and invoked with three arguments; (value, index|key, collection). + * The `callback` argument may also be the name of a property to count by (e.g. 'length'). + * + * @static + * @memberOf _ + * @category Collections + * @param {Array|Object|String} collection The collection to iterate over. + * @param {Function|String} callback|property The function called per iteration + * or property name to count by. + * @param {Mixed} [thisArg] The `this` binding of `callback`. + * @returns {Object} Returns the composed aggregate object. + * @example + * + * _.countBy([4.3, 6.1, 6.4], function(num) { return Math.floor(num); }); + * // => { '4': 1, '6': 2 } + * + * _.countBy([4.3, 6.1, 6.4], function(num) { return this.floor(num); }, Math); + * // => { '4': 1, '6': 2 } + * + * _.countBy(['one', 'two', 'three'], 'length'); + * // => { '3': 2, '5': 1 } + */ + function countBy(collection, callback, thisArg) { + var result = {}; + callback = createCallback(callback, thisArg); + forEach(collection, function(value, key, collection) { + key = callback(value, key, collection); + (hasOwnProperty.call(result, key) ? result[key]++ : result[key] = 1); + }); + return result; + } + + /** + * Checks if the `callback` returns a truthy value for **all** elements of a + * `collection`. The `callback` is bound to `thisArg` and invoked with three + * arguments; (value, index|key, collection). + * + * @static + * @memberOf _ + * @alias all + * @category Collections + * @param {Array|Object|String} collection The collection to iterate over. + * @param {Function} [callback=identity] The function called per iteration. + * @param {Mixed} [thisArg] The `this` binding of `callback`. + * @returns {Boolean} Returns `true` if all elements pass the callback check, + * else `false`. + * @example + * + * _.every([true, 1, null, 'yes'], Boolean); + * // => false + */ + function every(collection, callback, thisArg) { + var result = true; + callback = createCallback(callback, thisArg); + + if (isArray(collection)) { + var index = -1, + length = collection.length; + + while (++index < length) { + if (!(result = !!callback(collection[index], index, collection))) { + break; + } + } + } else { + forEach(collection, function(value, index, collection) { + return (result = !!callback(value, index, collection)); + }); + } + return result; + } + + /** + * Examines each element in a `collection`, returning an array of all elements + * the `callback` returns truthy for. The `callback` is bound to `thisArg` and + * invoked with three arguments; (value, index|key, collection). + * + * @static + * @memberOf _ + * @alias select + * @category Collections + * @param {Array|Object|String} collection The collection to iterate over. + * @param {Function} [callback=identity] The function called per iteration. + * @param {Mixed} [thisArg] The `this` binding of `callback`. + * @returns {Array} Returns a new array of elements that passed the callback check. + * @example + * + * var evens = _.filter([1, 2, 3, 4, 5, 6], function(num) { return num % 2 == 0; }); + * // => [2, 4, 6] + */ + function filter(collection, callback, thisArg) { + var result = []; + callback = createCallback(callback, thisArg); + forEach(collection, function(value, index, collection) { + if (callback(value, index, collection)) { + result.push(value); + } + }); + return result; + } + + /** + * Examines each element in a `collection`, returning the first one the `callback` + * returns truthy for. The function returns as soon as it finds an acceptable + * element, and does not iterate over the entire `collection`. The `callback` is + * bound to `thisArg` and invoked with three arguments; (value, index|key, collection). + * + * @static + * @memberOf _ + * @alias detect + * @category Collections + * @param {Array|Object|String} collection The collection to iterate over. + * @param {Function} callback The function called per iteration. + * @param {Mixed} [thisArg] The `this` binding of `callback`. + * @returns {Mixed} Returns the element that passed the callback check, + * else `undefined`. + * @example + * + * var even = _.find([1, 2, 3, 4, 5, 6], function(num) { return num % 2 == 0; }); + * // => 2 + */ + function find(collection, callback, thisArg) { + var result; + callback = createCallback(callback, thisArg); + forEach(collection, function(value, index, collection) { + if (callback(value, index, collection)) { + result = value; + return false; + } + }); + return result; + } + + /** + * Iterates over a `collection`, executing the `callback` for each element in + * the `collection`. The `callback` is bound to `thisArg` and invoked with three + * arguments; (value, index|key, collection). Callbacks may exit iteration early + * by explicitly returning `false`. + * + * @static + * @memberOf _ + * @alias each + * @category Collections + * @param {Array|Object|String} collection The collection to iterate over. + * @param {Function} callback The function called per iteration. + * @param {Mixed} [thisArg] The `this` binding of `callback`. + * @returns {Array|Object|String} Returns `collection`. + * @example + * + * _([1, 2, 3]).forEach(alert).join(','); + * // => alerts each number and returns '1,2,3' + * + * _.forEach({ 'one': 1, 'two': 2, 'three': 3 }, alert); + * // => alerts each number (order is not guaranteed) + */ + var forEach = createIterator(forEachIteratorOptions); + + /** + * Creates an object composed of keys returned from running each element of + * `collection` through a `callback`. The corresponding value of each key is an + * array of elements passed to `callback` that returned the key. The `callback` + * is bound to `thisArg` and invoked with three arguments; (value, index|key, collection). + * The `callback` argument may also be the name of a property to group by (e.g. 'length'). + * + * @static + * @memberOf _ + * @category Collections + * @param {Array|Object|String} collection The collection to iterate over. + * @param {Function|String} callback|property The function called per iteration + * or property name to group by. + * @param {Mixed} [thisArg] The `this` binding of `callback`. + * @returns {Object} Returns the composed aggregate object. + * @example + * + * _.groupBy([4.2, 6.1, 6.4], function(num) { return Math.floor(num); }); + * // => { '4': [4.2], '6': [6.1, 6.4] } + * + * _.groupBy([4.2, 6.1, 6.4], function(num) { return this.floor(num); }, Math); + * // => { '4': [4.2], '6': [6.1, 6.4] } + * + * _.groupBy(['one', 'two', 'three'], 'length'); + * // => { '3': ['one', 'two'], '5': ['three'] } + */ + function groupBy(collection, callback, thisArg) { + var result = {}; + callback = createCallback(callback, thisArg); + forEach(collection, function(value, key, collection) { + key = callback(value, key, collection); + (hasOwnProperty.call(result, key) ? result[key] : result[key] = []).push(value); + }); + return result; + } + + /** + * Invokes the method named by `methodName` on each element in the `collection`, + * returning an array of the results of each invoked method. Additional arguments + * will be passed to each invoked method. If `methodName` is a function it will + * be invoked for, and `this` bound to, each element in the `collection`. + * + * @static + * @memberOf _ + * @category Collections + * @param {Array|Object|String} collection The collection to iterate over. + * @param {Function|String} methodName The name of the method to invoke or + * the function invoked per iteration. + * @param {Mixed} [arg1, arg2, ...] Arguments to invoke the method with. + * @returns {Array} Returns a new array of the results of each invoked method. + * @example + * + * _.invoke([[5, 1, 7], [3, 2, 1]], 'sort'); + * // => [[1, 5, 7], [1, 2, 3]] + * + * _.invoke([123, 456], String.prototype.split, ''); + * // => [['1', '2', '3'], ['4', '5', '6']] + */ + function invoke(collection, methodName) { + var args = slice.call(arguments, 2), + isFunc = typeof methodName == 'function', + result = []; + + forEach(collection, function(value) { + result.push((isFunc ? methodName : value[methodName]).apply(value, args)); + }); + return result; + } + + /** + * Creates an array of values by running each element in the `collection` + * through a `callback`. The `callback` is bound to `thisArg` and invoked with + * three arguments; (value, index|key, collection). + * + * @static + * @memberOf _ + * @alias collect + * @category Collections + * @param {Array|Object|String} collection The collection to iterate over. + * @param {Function} [callback=identity] The function called per iteration. + * @param {Mixed} [thisArg] The `this` binding of `callback`. + * @returns {Array} Returns a new array of the results of each `callback` execution. + * @example + * + * _.map([1, 2, 3], function(num) { return num * 3; }); + * // => [3, 6, 9] + * + * _.map({ 'one': 1, 'two': 2, 'three': 3 }, function(num) { return num * 3; }); + * // => [3, 6, 9] (order is not guaranteed) + */ + function map(collection, callback, thisArg) { + var index = -1, + length = collection ? collection.length : 0, + result = Array(typeof length == 'number' ? length : 0); + + callback = createCallback(callback, thisArg); + if (isArray(collection)) { + while (++index < length) { + result[index] = callback(collection[index], index, collection); + } + } else { + forEach(collection, function(value, key, collection) { + result[++index] = callback(value, key, collection); + }); + } + return result; + } + + /** + * Retrieves the maximum value of an `array`. If `callback` is passed, + * it will be executed for each value in the `array` to generate the + * criterion by which the value is ranked. The `callback` is bound to + * `thisArg` and invoked with three arguments; (value, index, collection). + * + * @static + * @memberOf _ + * @category Collections + * @param {Array|Object|String} collection The collection to iterate over. + * @param {Function} [callback] The function called per iteration. + * @param {Mixed} [thisArg] The `this` binding of `callback`. + * @returns {Mixed} Returns the maximum value. + * @example + * + * var stooges = [ + * { 'name': 'moe', 'age': 40 }, + * { 'name': 'larry', 'age': 50 }, + * { 'name': 'curly', 'age': 60 } + * ]; + * + * _.max(stooges, function(stooge) { return stooge.age; }); + * // => { 'name': 'curly', 'age': 60 }; + */ + function max(collection, callback, thisArg) { + var computed = -Infinity, + index = -1, + length = collection ? collection.length : 0, + result = computed; + + if (callback || !isArray(collection)) { + callback = !callback && isString(collection) + ? charAtCallback + : createCallback(callback, thisArg); + + forEach(collection, function(value, index, collection) { + var current = callback(value, index, collection); + if (current > computed) { + computed = current; + result = value; + } + }); + } else { + while (++index < length) { + if (collection[index] > result) { + result = collection[index]; + } + } + } + return result; + } + + /** + * Retrieves the minimum value of an `array`. If `callback` is passed, + * it will be executed for each value in the `array` to generate the + * criterion by which the value is ranked. The `callback` is bound to `thisArg` + * and invoked with three arguments; (value, index, collection). + * + * @static + * @memberOf _ + * @category Collections + * @param {Array|Object|String} collection The collection to iterate over. + * @param {Function} [callback] The function called per iteration. + * @param {Mixed} [thisArg] The `this` binding of `callback`. + * @returns {Mixed} Returns the minimum value. + * @example + * + * _.min([10, 5, 100, 2, 1000]); + * // => 2 + */ + function min(collection, callback, thisArg) { + var computed = Infinity, + index = -1, + length = collection ? collection.length : 0, + result = computed; + + if (callback || !isArray(collection)) { + callback = !callback && isString(collection) + ? charAtCallback + : createCallback(callback, thisArg); + + forEach(collection, function(value, index, collection) { + var current = callback(value, index, collection); + if (current < computed) { + computed = current; + result = value; + } + }); + } else { + while (++index < length) { + if (collection[index] < result) { + result = collection[index]; + } + } + } + return result; + } + + /** + * Retrieves the value of a specified property from all elements in + * the `collection`. + * + * @static + * @memberOf _ + * @category Collections + * @param {Array|Object|String} collection The collection to iterate over. + * @param {String} property The property to pluck. + * @returns {Array} Returns a new array of property values. + * @example + * + * var stooges = [ + * { 'name': 'moe', 'age': 40 }, + * { 'name': 'larry', 'age': 50 }, + * { 'name': 'curly', 'age': 60 } + * ]; + * + * _.pluck(stooges, 'name'); + * // => ['moe', 'larry', 'curly'] + */ + function pluck(collection, property) { + var result = []; + forEach(collection, function(value) { + result.push(value[property]); + }); + return result; + } + + /** + * Boils down a `collection` to a single value. The initial state of the + * reduction is `accumulator` and each successive step of it should be returned + * by the `callback`. The `callback` is bound to `thisArg` and invoked with 4 + * arguments; for arrays they are (accumulator, value, index|key, collection). + * + * @static + * @memberOf _ + * @alias foldl, inject + * @category Collections + * @param {Array|Object|String} collection The collection to iterate over. + * @param {Function} callback The function called per iteration. + * @param {Mixed} [accumulator] Initial value of the accumulator. + * @param {Mixed} [thisArg] The `this` binding of `callback`. + * @returns {Mixed} Returns the accumulated value. + * @example + * + * var sum = _.reduce([1, 2, 3], function(memo, num) { return memo + num; }); + * // => 6 + */ + function reduce(collection, callback, accumulator, thisArg) { + var noaccum = arguments.length < 3; + callback = createCallback(callback, thisArg); + forEach(collection, function(value, index, collection) { + accumulator = noaccum + ? (noaccum = false, value) + : callback(accumulator, value, index, collection) + }); + return accumulator; + } + + /** + * The right-associative version of `_.reduce`. + * + * @static + * @memberOf _ + * @alias foldr + * @category Collections + * @param {Array|Object|String} collection The collection to iterate over. + * @param {Function} callback The function called per iteration. + * @param {Mixed} [accumulator] Initial value of the accumulator. + * @param {Mixed} [thisArg] The `this` binding of `callback`. + * @returns {Mixed} Returns the accumulated value. + * @example + * + * var list = [[0, 1], [2, 3], [4, 5]]; + * var flat = _.reduceRight(list, function(a, b) { return a.concat(b); }, []); + * // => [4, 5, 2, 3, 0, 1] + */ + function reduceRight(collection, callback, accumulator, thisArg) { + var iteratee = collection, + length = collection ? collection.length : 0, + noaccum = arguments.length < 3; + + if (typeof length != 'number') { + var props = keys(collection); + length = props.length; + } else if (noCharByIndex && isString(collection)) { + iteratee = collection.split(''); + } + forEach(collection, function(value, index, collection) { + index = props ? props[--length] : --length; + accumulator = noaccum + ? (noaccum = false, iteratee[index]) + : callback.call(thisArg, accumulator, iteratee[index], index, collection); + }); + return accumulator; + } + + /** + * The opposite of `_.filter`, this method returns the values of a + * `collection` that `callback` does **not** return truthy for. + * + * @static + * @memberOf _ + * @category Collections + * @param {Array|Object|String} collection The collection to iterate over. + * @param {Function} [callback=identity] The function called per iteration. + * @param {Mixed} [thisArg] The `this` binding of `callback`. + * @returns {Array} Returns a new array of elements that did **not** pass the + * callback check. + * @example + * + * var odds = _.reject([1, 2, 3, 4, 5, 6], function(num) { return num % 2 == 0; }); + * // => [1, 3, 5] + */ + function reject(collection, callback, thisArg) { + callback = createCallback(callback, thisArg); + return filter(collection, function(value, index, collection) { + return !callback(value, index, collection); + }); + } + + /** + * Creates an array of shuffled `array` values, using a version of the + * Fisher-Yates shuffle. See http://en.wikipedia.org/wiki/Fisher-Yates_shuffle. + * + * @static + * @memberOf _ + * @category Collections + * @param {Array|Object|String} collection The collection to shuffle. + * @returns {Array} Returns a new shuffled collection. + * @example + * + * _.shuffle([1, 2, 3, 4, 5, 6]); + * // => [4, 1, 6, 3, 5, 2] + */ + function shuffle(collection) { + var index = -1, + result = Array(collection ? collection.length : 0); + + forEach(collection, function(value) { + var rand = floor(nativeRandom() * (++index + 1)); + result[index] = result[rand]; + result[rand] = value; + }); + return result; + } + + /** + * Gets the size of the `collection` by returning `collection.length` for arrays + * and array-like objects or the number of own enumerable properties for objects. + * + * @static + * @memberOf _ + * @category Collections + * @param {Array|Object|String} collection The collection to inspect. + * @returns {Number} Returns `collection.length` or number of own enumerable properties. + * @example + * + * _.size([1, 2]); + * // => 2 + * + * _.size({ 'one': 1, 'two': 2, 'three': 3 }); + * // => 3 + * + * _.size('curly'); + * // => 5 + */ + function size(collection) { + var length = collection ? collection.length : 0; + return typeof length == 'number' ? length : keys(collection).length; + } + + /** + * Checks if the `callback` returns a truthy value for **any** element of a + * `collection`. The function returns as soon as it finds passing value, and + * does not iterate over the entire `collection`. The `callback` is bound to + * `thisArg` and invoked with three arguments; (value, index|key, collection). + * + * @static + * @memberOf _ + * @alias any + * @category Collections + * @param {Array|Object|String} collection The collection to iterate over. + * @param {Function} [callback=identity] The function called per iteration. + * @param {Mixed} [thisArg] The `this` binding of `callback`. + * @returns {Boolean} Returns `true` if any element passes the callback check, + * else `false`. + * @example + * + * _.some([null, 0, 'yes', false]); + * // => true + */ + function some(collection, callback, thisArg) { + var result; + callback = createCallback(callback, thisArg); + + if (isArray(collection)) { + var index = -1, + length = collection.length; + + while (++index < length) { + if (result = callback(collection[index], index, collection)) { + break; + } + } + } else { + forEach(collection, function(value, index, collection) { + return !(result = callback(value, index, collection)); + }); + } + return !!result; + } + + /** + * Creates an array, stable sorted in ascending order by the results of + * running each element of `collection` through a `callback`. The `callback` + * is bound to `thisArg` and invoked with three arguments; (value, index|key, collection). + * The `callback` argument may also be the name of a property to sort by (e.g. 'length'). + * + * @static + * @memberOf _ + * @category Collections + * @param {Array|Object|String} collection The collection to iterate over. + * @param {Function|String} callback|property The function called per iteration + * or property name to sort by. + * @param {Mixed} [thisArg] The `this` binding of `callback`. + * @returns {Array} Returns a new array of sorted elements. + * @example + * + * _.sortBy([1, 2, 3], function(num) { return Math.sin(num); }); + * // => [3, 1, 2] + * + * _.sortBy([1, 2, 3], function(num) { return this.sin(num); }, Math); + * // => [3, 1, 2] + * + * _.sortBy(['larry', 'brendan', 'moe'], 'length'); + * // => ['moe', 'larry', 'brendan'] + */ + function sortBy(collection, callback, thisArg) { + var result = []; + callback = createCallback(callback, thisArg); + forEach(collection, function(value, index, collection) { + result.push({ + 'criteria': callback(value, index, collection), + 'index': index, + 'value': value + }); + }); + + var length = result.length; + result.sort(compareAscending); + while (length--) { + result[length] = result[length].value; + } + return result; + } + + /** + * Converts the `collection`, to an array. + * + * @static + * @memberOf _ + * @category Collections + * @param {Array|Object|String} collection The collection to convert. + * @returns {Array} Returns the new converted array. + * @example + * + * (function() { return _.toArray(arguments).slice(1); })(1, 2, 3, 4); + * // => [2, 3, 4] + */ + function toArray(collection) { + if (collection && typeof collection.length == 'number') { + return (noArraySliceOnStrings ? isString(collection) : typeof collection == 'string') + ? collection.split('') + : slice.call(collection); + } + return values(collection); + } + + /** + * Examines each element in a `collection`, returning an array of all elements + * that contain the given `properties`. + * + * @static + * @memberOf _ + * @category Collections + * @param {Array|Object|String} collection The collection to iterate over. + * @param {Object} properties The object of property values to filter by. + * @returns {Array} Returns a new array of elements that contain the given `properties`. + * @example + * + * var stooges = [ + * { 'name': 'moe', 'age': 40 }, + * { 'name': 'larry', 'age': 50 }, + * { 'name': 'curly', 'age': 60 } + * ]; + * + * _.where(stooges, { 'age': 40 }); + * // => [{ 'name': 'moe', 'age': 40 }] + */ + function where(collection, properties) { + var props = []; + forIn(properties, function(value, prop) { + props.push(prop); + }); + return filter(collection, function(object) { + var length = props.length; + while (length--) { + var result = object[props[length]] === properties[props[length]]; + if (!result) { + break; + } + } + return !!result; + }); + } + + /*--------------------------------------------------------------------------*/ + + /** + * Creates an array with all falsey values of `array` removed. The values + * `false`, `null`, `0`, `""`, `undefined` and `NaN` are all falsey. + * + * @static + * @memberOf _ + * @category Arrays + * @param {Array} array The array to compact. + * @returns {Array} Returns a new filtered array. + * @example + * + * _.compact([0, 1, false, 2, '', 3]); + * // => [1, 2, 3] + */ + function compact(array) { + var index = -1, + length = array ? array.length : 0, + result = []; + + while (++index < length) { + var value = array[index]; + if (value) { + result.push(value); + } + } + return result; + } + + /** + * Creates an array of `array` elements not present in the other arrays + * using strict equality for comparisons, i.e. `===`. + * + * @static + * @memberOf _ + * @category Arrays + * @param {Array} array The array to process. + * @param {Array} [array1, array2, ...] Arrays to check. + * @returns {Array} Returns a new array of `array` elements not present in the + * other arrays. + * @example + * + * _.difference([1, 2, 3, 4, 5], [5, 2, 10]); + * // => [1, 3, 4] + */ + function difference(array) { + var index = -1, + length = array ? array.length : 0, + flattened = concat.apply(arrayRef, arguments), + contains = cachedContains(flattened, length), + result = []; + + while (++index < length) { + var value = array[index]; + if (!contains(value)) { + result.push(value); + } + } + return result; + } + + /** + * Gets the first element of the `array`. Pass `n` to return the first `n` + * elements of the `array`. + * + * @static + * @memberOf _ + * @alias head, take + * @category Arrays + * @param {Array} array The array to query. + * @param {Number} [n] The number of elements to return. + * @param- {Object} [guard] Internally used to allow this method to work with + * others like `_.map` without using their callback `index` argument for `n`. + * @returns {Mixed} Returns the first element or an array of the first `n` + * elements of `array`. + * @example + * + * _.first([5, 4, 3, 2, 1]); + * // => 5 + */ + function first(array, n, guard) { + if (array) { + return (n == null || guard) ? array[0] : slice.call(array, 0, n); + } + } + + /** + * Flattens a nested array (the nesting can be to any depth). If `shallow` is + * truthy, `array` will only be flattened a single level. + * + * @static + * @memberOf _ + * @category Arrays + * @param {Array} array The array to compact. + * @param {Boolean} shallow A flag to indicate only flattening a single level. + * @returns {Array} Returns a new flattened array. + * @example + * + * _.flatten([1, [2], [3, [[4]]]]); + * // => [1, 2, 3, 4]; + * + * _.flatten([1, [2], [3, [[4]]]], true); + * // => [1, 2, 3, [[4]]]; + */ + function flatten(array, shallow) { + var index = -1, + length = array ? array.length : 0, + result = []; + + while (++index < length) { + var value = array[index]; + + // recursively flatten arrays (susceptible to call stack limits) + if (isArray(value)) { + push.apply(result, shallow ? value : flatten(value)); + } else { + result.push(value); + } + } + return result; + } + + /** + * Gets the index at which the first occurrence of `value` is found using + * strict equality for comparisons, i.e. `===`. If the `array` is already + * sorted, passing `true` for `fromIndex` will run a faster binary search. + * + * @static + * @memberOf _ + * @category Arrays + * @param {Array} array The array to search. + * @param {Mixed} value The value to search for. + * @param {Boolean|Number} [fromIndex=0] The index to search from or `true` to + * perform a binary search on a sorted `array`. + * @returns {Number} Returns the index of the matched value or `-1`. + * @example + * + * _.indexOf([1, 2, 3, 1, 2, 3], 2); + * // => 1 + * + * _.indexOf([1, 2, 3, 1, 2, 3], 2, 3); + * // => 4 + * + * _.indexOf([1, 1, 2, 2, 3, 3], 2, true); + * // => 2 + */ + function indexOf(array, value, fromIndex) { + var index = -1, + length = array ? array.length : 0; + + if (typeof fromIndex == 'number') { + index = (fromIndex < 0 ? nativeMax(0, length + fromIndex) : fromIndex || 0) - 1; + } else if (fromIndex) { + index = sortedIndex(array, value); + return array[index] === value ? index : -1; + } + while (++index < length) { + if (array[index] === value) { + return index; + } + } + return -1; + } + + /** + * Gets all but the last element of `array`. Pass `n` to exclude the last `n` + * elements from the result. + * + * @static + * @memberOf _ + * @category Arrays + * @param {Array} array The array to query. + * @param {Number} [n=1] The number of elements to exclude. + * @param- {Object} [guard] Internally used to allow this method to work with + * others like `_.map` without using their callback `index` argument for `n`. + * @returns {Array} Returns all but the last element or `n` elements of `array`. + * @example + * + * _.initial([3, 2, 1]); + * // => [3, 2] + */ + function initial(array, n, guard) { + return array + ? slice.call(array, 0, -((n == null || guard) ? 1 : n)) + : []; + } + + /** + * Computes the intersection of all the passed-in arrays using strict equality + * for comparisons, i.e. `===`. + * + * @static + * @memberOf _ + * @category Arrays + * @param {Array} [array1, array2, ...] Arrays to process. + * @returns {Array} Returns a new array of unique elements, in order, that are + * present in **all** of the arrays. + * @example + * + * _.intersection([1, 2, 3], [101, 2, 1, 10], [2, 1]); + * // => [1, 2] + */ + function intersection(array) { + var args = arguments, + argsLength = args.length, + cache = {}, + result = []; + + forEach(array, function(value) { + if (indexOf(result, value) < 0) { + var length = argsLength; + while (--length) { + if (!(cache[length] || (cache[length] = cachedContains(args[length])))(value)) { + return; + } + } + result.push(value); + } + }); + return result; + } + + /** + * Gets the last element of the `array`. Pass `n` to return the last `n` + * elements of the `array`. + * + * @static + * @memberOf _ + * @category Arrays + * @param {Array} array The array to query. + * @param {Number} [n] The number of elements to return. + * @param- {Object} [guard] Internally used to allow this method to work with + * others like `_.map` without using their callback `index` argument for `n`. + * @returns {Mixed} Returns the last element or an array of the last `n` + * elements of `array`. + * @example + * + * _.last([3, 2, 1]); + * // => 1 + */ + function last(array, n, guard) { + if (array) { + var length = array.length; + return (n == null || guard) ? array[length - 1] : slice.call(array, -n || length); + } + } + + /** + * Gets the index at which the last occurrence of `value` is found using strict + * equality for comparisons, i.e. `===`. If `fromIndex` is negative, it is used + * as the offset from the end of the collection. + * + * @static + * @memberOf _ + * @category Arrays + * @param {Array} array The array to search. + * @param {Mixed} value The value to search for. + * @param {Number} [fromIndex=array.length-1] The index to search from. + * @returns {Number} Returns the index of the matched value or `-1`. + * @example + * + * _.lastIndexOf([1, 2, 3, 1, 2, 3], 2); + * // => 4 + * + * _.lastIndexOf([1, 2, 3, 1, 2, 3], 2, 3); + * // => 1 + */ + function lastIndexOf(array, value, fromIndex) { + var index = array ? array.length : 0; + if (typeof fromIndex == 'number') { + index = (fromIndex < 0 ? nativeMax(0, index + fromIndex) : nativeMin(fromIndex, index - 1)) + 1; + } + while (index--) { + if (array[index] === value) { + return index; + } + } + return -1; + } + + /** + * Creates an object composed from arrays of `keys` and `values`. Pass either + * a single two dimensional array, i.e. `[[key1, value1], [key2, value2]]`, or + * two arrays, one of `keys` and one of corresponding `values`. + * + * @static + * @memberOf _ + * @category Arrays + * @param {Array} keys The array of keys. + * @param {Array} [values=[]] The array of values. + * @returns {Object} Returns an object composed of the given keys and + * corresponding values. + * @example + * + * _.object(['moe', 'larry', 'curly'], [30, 40, 50]); + * // => { 'moe': 30, 'larry': 40, 'curly': 50 } + */ + function object(keys, values) { + var index = -1, + length = keys ? keys.length : 0, + result = {}; + + while (++index < length) { + var key = keys[index]; + if (values) { + result[key] = values[index]; + } else { + result[key[0]] = key[1]; + } + } + return result; + } + + /** + * Creates an array of numbers (positive and/or negative) progressing from + * `start` up to but not including `stop`. This method is a port of Python's + * `range()` function. See http://docs.python.org/library/functions.html#range. + * + * @static + * @memberOf _ + * @category Arrays + * @param {Number} [start=0] The start of the range. + * @param {Number} end The end of the range. + * @param {Number} [step=1] The value to increment or descrement by. + * @returns {Array} Returns a new range array. + * @example + * + * _.range(10); + * // => [0, 1, 2, 3, 4, 5, 6, 7, 8, 9] + * + * _.range(1, 11); + * // => [1, 2, 3, 4, 5, 6, 7, 8, 9, 10] + * + * _.range(0, 30, 5); + * // => [0, 5, 10, 15, 20, 25] + * + * _.range(0, -10, -1); + * // => [0, -1, -2, -3, -4, -5, -6, -7, -8, -9] + * + * _.range(0); + * // => [] + */ + function range(start, end, step) { + start = +start || 0; + step = +step || 1; + + if (end == null) { + end = start; + start = 0; + } + // use `Array(length)` so V8 will avoid the slower "dictionary" mode + // http://www.youtube.com/watch?v=XAqIpGU8ZZk#t=16m27s + var index = -1, + length = nativeMax(0, ceil((end - start) / step)), + result = Array(length); + + while (++index < length) { + result[index] = start; + start += step; + } + return result; + } + + /** + * The opposite of `_.initial`, this method gets all but the first value of + * `array`. Pass `n` to exclude the first `n` values from the result. + * + * @static + * @memberOf _ + * @alias drop, tail + * @category Arrays + * @param {Array} array The array to query. + * @param {Number} [n=1] The number of elements to exclude. + * @param- {Object} [guard] Internally used to allow this method to work with + * others like `_.map` without using their callback `index` argument for `n`. + * @returns {Array} Returns all but the first value or `n` values of `array`. + * @example + * + * _.rest([3, 2, 1]); + * // => [2, 1] + */ + function rest(array, n, guard) { + return array + ? slice.call(array, (n == null || guard) ? 1 : n) + : []; + } + + /** + * Uses a binary search to determine the smallest index at which the `value` + * should be inserted into `array` in order to maintain the sort order of the + * sorted `array`. If `callback` is passed, it will be executed for `value` and + * each element in `array` to compute their sort ranking. The `callback` is + * bound to `thisArg` and invoked with one argument; (value). The `callback` + * argument may also be the name of a property to order by. + * + * @static + * @memberOf _ + * @category Arrays + * @param {Array} array The array to iterate over. + * @param {Mixed} value The value to evaluate. + * @param {Function|String} [callback=identity|property] The function called + * per iteration or property name to order by. + * @param {Mixed} [thisArg] The `this` binding of `callback`. + * @returns {Number} Returns the index at which the value should be inserted + * into `array`. + * @example + * + * _.sortedIndex([20, 30, 50], 40); + * // => 2 + * + * _.sortedIndex([{ 'x': 20 }, { 'x': 30 }, { 'x': 50 }], { 'x': 40 }, 'x'); + * // => 2 + * + * var dict = { + * 'wordToNumber': { 'twenty': 20, 'thirty': 30, 'fourty': 40, 'fifty': 50 } + * }; + * + * _.sortedIndex(['twenty', 'thirty', 'fifty'], 'fourty', function(word) { + * return dict.wordToNumber[word]; + * }); + * // => 2 + * + * _.sortedIndex(['twenty', 'thirty', 'fifty'], 'fourty', function(word) { + * return this.wordToNumber[word]; + * }, dict); + * // => 2 + */ + function sortedIndex(array, value, callback, thisArg) { + var low = 0, + high = array ? array.length : low; + + // explicitly reference `identity` for better engine inlining + callback = callback ? createCallback(callback, thisArg) : identity; + value = callback(value); + while (low < high) { + var mid = (low + high) >>> 1; + callback(array[mid]) < value + ? low = mid + 1 + : high = mid; + } + return low; + } + + /** + * Computes the union of the passed-in arrays using strict equality for + * comparisons, i.e. `===`. + * + * @static + * @memberOf _ + * @category Arrays + * @param {Array} [array1, array2, ...] Arrays to process. + * @returns {Array} Returns a new array of unique values, in order, that are + * present in one or more of the arrays. + * @example + * + * _.union([1, 2, 3], [101, 2, 1, 10], [2, 1]); + * // => [1, 2, 3, 101, 10] + */ + function union() { + return uniq(concat.apply(arrayRef, arguments)); + } + + /** + * Creates a duplicate-value-free version of the `array` using strict equality + * for comparisons, i.e. `===`. If the `array` is already sorted, passing `true` + * for `isSorted` will run a faster algorithm. If `callback` is passed, each + * element of `array` is passed through a callback` before uniqueness is computed. + * The `callback` is bound to `thisArg` and invoked with three arguments; (value, index, array). + * + * @static + * @memberOf _ + * @alias unique + * @category Arrays + * @param {Array} array The array to process. + * @param {Boolean} [isSorted=false] A flag to indicate that the `array` is already sorted. + * @param {Function} [callback=identity] The function called per iteration. + * @param {Mixed} [thisArg] The `this` binding of `callback`. + * @returns {Array} Returns a duplicate-value-free array. + * @example + * + * _.uniq([1, 2, 1, 3, 1]); + * // => [1, 2, 3] + * + * _.uniq([1, 1, 2, 2, 3], true); + * // => [1, 2, 3] + * + * _.uniq([1, 2, 1.5, 3, 2.5], function(num) { return Math.floor(num); }); + * // => [1, 2, 3] + * + * _.uniq([1, 2, 1.5, 3, 2.5], function(num) { return this.floor(num); }, Math); + * // => [1, 2, 3] + */ + function uniq(array, isSorted, callback, thisArg) { + var index = -1, + length = array ? array.length : 0, + result = [], + seen = result; + + // juggle arguments + if (typeof isSorted == 'function') { + thisArg = callback; + callback = isSorted; + isSorted = false; + } + // init value cache for large arrays + var isLarge = !isSorted && length > 74; + if (isLarge) { + var cache = {}; + } + if (callback) { + seen = []; + callback = createCallback(callback, thisArg); + } + while (++index < length) { + var value = array[index], + computed = callback ? callback(value, index, array) : value; + + if (isLarge) { + // manually coerce `computed` to a string because `hasOwnProperty`, in + // some older versions of Firefox, coerces objects incorrectly + seen = hasOwnProperty.call(cache, computed + '') ? cache[computed] : (cache[computed] = []); + } + if (isSorted + ? !index || seen[seen.length - 1] !== computed + : indexOf(seen, computed) < 0 + ) { + if (callback || isLarge) { + seen.push(computed); + } + result.push(value); + } + } + return result; + } + + /** + * Creates an array with all occurrences of the passed values removed using + * strict equality for comparisons, i.e. `===`. + * + * @static + * @memberOf _ + * @category Arrays + * @param {Array} array The array to filter. + * @param {Mixed} [value1, value2, ...] Values to remove. + * @returns {Array} Returns a new filtered array. + * @example + * + * _.without([1, 2, 1, 0, 3, 1, 4], 0, 1); + * // => [2, 3, 4] + */ + function without(array) { + var index = -1, + length = array ? array.length : 0, + contains = cachedContains(arguments, 1, 20), + result = []; + + while (++index < length) { + var value = array[index]; + if (!contains(value)) { + result.push(value); + } + } + return result; + } + + /** + * Groups the elements of each array at their corresponding indexes. Useful for + * separate data sources that are coordinated through matching array indexes. + * For a matrix of nested arrays, `_.zip.apply(...)` can transpose the matrix + * in a similar fashion. + * + * @static + * @memberOf _ + * @category Arrays + * @param {Array} [array1, array2, ...] Arrays to process. + * @returns {Array} Returns a new array of grouped elements. + * @example + * + * _.zip(['moe', 'larry', 'curly'], [30, 40, 50], [true, false, false]); + * // => [['moe', 30, true], ['larry', 40, false], ['curly', 50, false]] + */ + function zip(array) { + var index = -1, + length = array ? max(pluck(arguments, 'length')) : 0, + result = Array(length); + + while (++index < length) { + result[index] = pluck(arguments, index); + } + return result; + } + + /*--------------------------------------------------------------------------*/ + + /** + * Creates a function that is restricted to executing `func` only after it is + * called `n` times. The `func` is executed with the `this` binding of the + * created function. + * + * @static + * @memberOf _ + * @category Functions + * @param {Number} n The number of times the function must be called before + * it is executed. + * @param {Function} func The function to restrict. + * @returns {Function} Returns the new restricted function. + * @example + * + * var renderNotes = _.after(notes.length, render); + * _.forEach(notes, function(note) { + * note.asyncSave({ 'success': renderNotes }); + * }); + * // `renderNotes` is run once, after all notes have saved + */ + function after(n, func) { + if (n < 1) { + return func(); + } + return function() { + if (--n < 1) { + return func.apply(this, arguments); + } + }; + } + + /** + * Creates a function that, when called, invokes `func` with the `this` + * binding of `thisArg` and prepends any additional `bind` arguments to those + * passed to the bound function. + * + * @static + * @memberOf _ + * @category Functions + * @param {Function} func The function to bind. + * @param {Mixed} [thisArg] The `this` binding of `func`. + * @param {Mixed} [arg1, arg2, ...] Arguments to be partially applied. + * @returns {Function} Returns the new bound function. + * @example + * + * var func = function(greeting) { + * return greeting + ' ' + this.name; + * }; + * + * func = _.bind(func, { 'name': 'moe' }, 'hi'); + * func(); + * // => 'hi moe' + */ + function bind(func, thisArg) { + // use `Function#bind` if it exists and is fast + // (in V8 `Function#bind` is slower except when partially applied) + return isBindFast || (nativeBind && arguments.length > 2) + ? nativeBind.call.apply(nativeBind, arguments) + : createBound(func, thisArg, slice.call(arguments, 2)); + } + + /** + * Binds methods on `object` to `object`, overwriting the existing method. + * If no method names are provided, all the function properties of `object` + * will be bound. + * + * @static + * @memberOf _ + * @category Functions + * @param {Object} object The object to bind and assign the bound methods to. + * @param {String} [methodName1, methodName2, ...] Method names on the object to bind. + * @returns {Object} Returns `object`. + * @example + * + * var buttonView = { + * 'label': 'lodash', + * 'onClick': function() { alert('clicked: ' + this.label); } + * }; + * + * _.bindAll(buttonView); + * jQuery('#lodash_button').on('click', buttonView.onClick); + * // => When the button is clicked, `this.label` will have the correct value + */ + function bindAll(object) { + var funcs = arguments, + index = funcs.length > 1 ? 0 : (funcs = functions(object), -1), + length = funcs.length; + + while (++index < length) { + var key = funcs[index]; + object[key] = bind(object[key], object); + } + return object; + } + + /** + * Creates a function that is the composition of the passed functions, + * where each function consumes the return value of the function that follows. + * In math terms, composing the functions `f()`, `g()`, and `h()` produces `f(g(h()))`. + * Each function is executed with the `this` binding of the composed function. + * + * @static + * @memberOf _ + * @category Functions + * @param {Function} [func1, func2, ...] Functions to compose. + * @returns {Function} Returns the new composed function. + * @example + * + * var greet = function(name) { return 'hi: ' + name; }; + * var exclaim = function(statement) { return statement + '!'; }; + * var welcome = _.compose(exclaim, greet); + * welcome('moe'); + * // => 'hi: moe!' + */ + function compose() { + var funcs = arguments; + return function() { + var args = arguments, + length = funcs.length; + + while (length--) { + args = [funcs[length].apply(this, args)]; + } + return args[0]; + }; + } + + /** + * Creates a function that will delay the execution of `func` until after + * `wait` milliseconds have elapsed since the last time it was invoked. Pass + * `true` for `immediate` to cause debounce to invoke `func` on the leading, + * instead of the trailing, edge of the `wait` timeout. Subsequent calls to + * the debounced function will return the result of the last `func` call. + * + * @static + * @memberOf _ + * @category Functions + * @param {Function} func The function to debounce. + * @param {Number} wait The number of milliseconds to delay. + * @param {Boolean} immediate A flag to indicate execution is on the leading + * edge of the timeout. + * @returns {Function} Returns the new debounced function. + * @example + * + * var lazyLayout = _.debounce(calculateLayout, 300); + * jQuery(window).on('resize', lazyLayout); + */ + function debounce(func, wait, immediate) { + var args, + result, + thisArg, + timeoutId; + + function delayed() { + timeoutId = null; + if (!immediate) { + result = func.apply(thisArg, args); + } + } + return function() { + var isImmediate = immediate && !timeoutId; + args = arguments; + thisArg = this; + + clearTimeout(timeoutId); + timeoutId = setTimeout(delayed, wait); + + if (isImmediate) { + result = func.apply(thisArg, args); + } + return result; + }; + } + + /** + * Executes the `func` function after `wait` milliseconds. Additional arguments + * will be passed to `func` when it is invoked. + * + * @static + * @memberOf _ + * @category Functions + * @param {Function} func The function to delay. + * @param {Number} wait The number of milliseconds to delay execution. + * @param {Mixed} [arg1, arg2, ...] Arguments to invoke the function with. + * @returns {Number} Returns the `setTimeout` timeout id. + * @example + * + * var log = _.bind(console.log, console); + * _.delay(log, 1000, 'logged later'); + * // => 'logged later' (Appears after one second.) + */ + function delay(func, wait) { + var args = slice.call(arguments, 2); + return setTimeout(function() { func.apply(undefined, args); }, wait); + } + + /** + * Defers executing the `func` function until the current call stack has cleared. + * Additional arguments will be passed to `func` when it is invoked. + * + * @static + * @memberOf _ + * @category Functions + * @param {Function} func The function to defer. + * @param {Mixed} [arg1, arg2, ...] Arguments to invoke the function with. + * @returns {Number} Returns the `setTimeout` timeout id. + * @example + * + * _.defer(function() { alert('deferred'); }); + * // returns from the function before `alert` is called + */ + function defer(func) { + var args = slice.call(arguments, 1); + return setTimeout(function() { func.apply(undefined, args); }, 1); + } + + /** + * Creates a function that, when called, invokes `object[methodName]` and + * prepends any additional `lateBind` arguments to those passed to the bound + * function. This method differs from `_.bind` by allowing bound functions to + * reference methods that will be redefined or don't yet exist. + * + * @static + * @memberOf _ + * @category Functions + * @param {Object} object The object the method belongs to. + * @param {String} methodName The method name. + * @param {Mixed} [arg1, arg2, ...] Arguments to be partially applied. + * @returns {Function} Returns the new bound function. + * @example + * + * var object = { + * 'name': 'moe', + * 'greet': function(greeting) { + * return greeting + ' ' + this.name; + * } + * }; + * + * var func = _.lateBind(object, 'greet', 'hi'); + * func(); + * // => 'hi moe' + * + * object.greet = function(greeting) { + * return greeting + ', ' + this.name + '!'; + * }; + * + * func(); + * // => 'hi, moe!' + */ + function lateBind(object, methodName) { + return createBound(methodName, object, slice.call(arguments, 2)); + } + + /** + * Creates a function that memoizes the result of `func`. If `resolver` is + * passed, it will be used to determine the cache key for storing the result + * based on the arguments passed to the memoized function. By default, the first + * argument passed to the memoized function is used as the cache key. The `func` + * is executed with the `this` binding of the memoized function. + * + * @static + * @memberOf _ + * @category Functions + * @param {Function} func The function to have its output memoized. + * @param {Function} [resolver] A function used to resolve the cache key. + * @returns {Function} Returns the new memoizing function. + * @example + * + * var fibonacci = _.memoize(function(n) { + * return n < 2 ? n : fibonacci(n - 1) + fibonacci(n - 2); + * }); + */ + function memoize(func, resolver) { + var cache = {}; + return function() { + var key = resolver ? resolver.apply(this, arguments) : arguments[0]; + return hasOwnProperty.call(cache, key) + ? cache[key] + : (cache[key] = func.apply(this, arguments)); + }; + } + + /** + * Creates a function that is restricted to execute `func` once. Repeat calls to + * the function will return the value of the first call. The `func` is executed + * with the `this` binding of the created function. + * + * @static + * @memberOf _ + * @category Functions + * @param {Function} func The function to restrict. + * @returns {Function} Returns the new restricted function. + * @example + * + * var initialize = _.once(createApplication); + * initialize(); + * initialize(); + * // Application is only created once. + */ + function once(func) { + var result, + ran = false; + + return function() { + if (ran) { + return result; + } + ran = true; + result = func.apply(this, arguments); + + // clear the `func` variable so the function may be garbage collected + func = null; + return result; + }; + } + + /** + * Creates a function that, when called, invokes `func` with any additional + * `partial` arguments prepended to those passed to the new function. This + * method is similar to `bind`, except it does **not** alter the `this` binding. + * + * @static + * @memberOf _ + * @category Functions + * @param {Function} func The function to partially apply arguments to. + * @param {Mixed} [arg1, arg2, ...] Arguments to be partially applied. + * @returns {Function} Returns the new partially applied function. + * @example + * + * var greet = function(greeting, name) { return greeting + ': ' + name; }; + * var hi = _.partial(greet, 'hi'); + * hi('moe'); + * // => 'hi: moe' + */ + function partial(func) { + return createBound(func, slice.call(arguments, 1)); + } + + /** + * Creates a function that, when executed, will only call the `func` + * function at most once per every `wait` milliseconds. If the throttled + * function is invoked more than once during the `wait` timeout, `func` will + * also be called on the trailing edge of the timeout. Subsequent calls to the + * throttled function will return the result of the last `func` call. + * + * @static + * @memberOf _ + * @category Functions + * @param {Function} func The function to throttle. + * @param {Number} wait The number of milliseconds to throttle executions to. + * @returns {Function} Returns the new throttled function. + * @example + * + * var throttled = _.throttle(updatePosition, 100); + * jQuery(window).on('scroll', throttled); + */ + function throttle(func, wait) { + var args, + result, + thisArg, + timeoutId, + lastCalled = 0; + + function trailingCall() { + lastCalled = new Date; + timeoutId = null; + result = func.apply(thisArg, args); + } + return function() { + var now = new Date, + remaining = wait - (now - lastCalled); + + args = arguments; + thisArg = this; + + if (remaining <= 0) { + clearTimeout(timeoutId); + lastCalled = now; + result = func.apply(thisArg, args); + } + else if (!timeoutId) { + timeoutId = setTimeout(trailingCall, remaining); + } + return result; + }; + } + + /** + * Creates a function that passes `value` to the `wrapper` function as its + * first argument. Additional arguments passed to the function are appended + * to those passed to the `wrapper` function. The `wrapper` is executed with + * the `this` binding of the created function. + * + * @static + * @memberOf _ + * @category Functions + * @param {Mixed} value The value to wrap. + * @param {Function} wrapper The wrapper function. + * @returns {Function} Returns the new function. + * @example + * + * var hello = function(name) { return 'hello ' + name; }; + * hello = _.wrap(hello, function(func) { + * return 'before, ' + func('moe') + ', after'; + * }); + * hello(); + * // => 'before, hello moe, after' + */ + function wrap(value, wrapper) { + return function() { + var args = [value]; + push.apply(args, arguments); + return wrapper.apply(this, args); + }; + } + + /*--------------------------------------------------------------------------*/ + + /** + * Converts the characters `&`, `<`, `>`, `"`, and `'` in `string` to their + * corresponding HTML entities. + * + * @static + * @memberOf _ + * @category Utilities + * @param {String} string The string to escape. + * @returns {String} Returns the escaped string. + * @example + * + * _.escape('Moe, Larry & Curly'); + * // => "Moe, Larry & Curly" + */ + function escape(string) { + return string == null ? '' : (string + '').replace(reUnescapedHtml, escapeHtmlChar); + } + + /** + * This function returns the first argument passed to it. + * + * Note: It is used throughout Lo-Dash as a default callback. + * + * @static + * @memberOf _ + * @category Utilities + * @param {Mixed} value Any value. + * @returns {Mixed} Returns `value`. + * @example + * + * var moe = { 'name': 'moe' }; + * moe === _.identity(moe); + * // => true + */ + function identity(value) { + return value; + } + + /** + * Adds functions properties of `object` to the `lodash` function and chainable + * wrapper. + * + * @static + * @memberOf _ + * @category Utilities + * @param {Object} object The object of function properties to add to `lodash`. + * @example + * + * _.mixin({ + * 'capitalize': function(string) { + * return string.charAt(0).toUpperCase() + string.slice(1).toLowerCase(); + * } + * }); + * + * _.capitalize('larry'); + * // => 'Larry' + * + * _('curly').capitalize(); + * // => 'Curly' + */ + function mixin(object) { + forEach(functions(object), function(methodName) { + var func = lodash[methodName] = object[methodName]; + + lodash.prototype[methodName] = function() { + var args = [this.__wrapped__]; + push.apply(args, arguments); + + var result = func.apply(lodash, args); + if (this.__chain__) { + result = new lodash(result); + result.__chain__ = true; + } + return result; + }; + }); + } + + /** + * Reverts the '_' variable to its previous value and returns a reference to + * the `lodash` function. + * + * @static + * @memberOf _ + * @category Utilities + * @returns {Function} Returns the `lodash` function. + * @example + * + * var lodash = _.noConflict(); + */ + function noConflict() { + window._ = oldDash; + return this; + } + + /** + * Produces a random number between `min` and `max` (inclusive). If only one + * argument is passed, a number between `0` and the given number will be returned. + * + * @static + * @memberOf _ + * @category Utilities + * @param {Number} [min=0] The minimum possible value. + * @param {Number} [max=1] The maximum possible value. + * @returns {Number} Returns a random number. + * @example + * + * _.random(0, 5); + * // => a number between 1 and 5 + * + * _.random(5); + * // => also a number between 1 and 5 + */ + function random(min, max) { + if (min == null && max == null) { + max = 1; + } + min = +min || 0; + if (max == null) { + max = min; + min = 0; + } + return min + floor(nativeRandom() * ((+max || 0) - min + 1)); + } + + /** + * Resolves the value of `property` on `object`. If `property` is a function + * it will be invoked and its result returned, else the property value is + * returned. If `object` is falsey, then `null` is returned. + * + * @deprecated + * @static + * @memberOf _ + * @category Utilities + * @param {Object} object The object to inspect. + * @param {String} property The property to get the value of. + * @returns {Mixed} Returns the resolved value. + * @example + * + * var object = { + * 'cheese': 'crumpets', + * 'stuff': function() { + * return 'nonsense'; + * } + * }; + * + * _.result(object, 'cheese'); + * // => 'crumpets' + * + * _.result(object, 'stuff'); + * // => 'nonsense' + */ + function result(object, property) { + // based on Backbone's private `getValue` function + // https://github.com/documentcloud/backbone/blob/0.9.2/backbone.js#L1419-1424 + var value = object ? object[property] : null; + return isFunction(value) ? object[property]() : value; + } + + /** + * A micro-templating method that handles arbitrary delimiters, preserves + * whitespace, and correctly escapes quotes within interpolated code. + * + * Note: In the development build `_.template` utilizes sourceURLs for easier + * debugging. See http://www.html5rocks.com/en/tutorials/developertools/sourcemaps/#toc-sourceurl + * + * Note: Lo-Dash may be used in Chrome extensions by either creating a `lodash csp` + * build and avoiding `_.template` use, or loading Lo-Dash in a sandboxed page. + * See http://developer.chrome.com/trunk/extensions/sandboxingEval.html + * + * @static + * @memberOf _ + * @category Utilities + * @param {String} text The template text. + * @param {Obect} data The data object used to populate the text. + * @param {Object} options The options object. + * escape - The "escape" delimiter regexp. + * evaluate - The "evaluate" delimiter regexp. + * interpolate - The "interpolate" delimiter regexp. + * sourceURL - The sourceURL of the template's compiled source. + * variable - The data object variable name. + * + * @returns {Function|String} Returns a compiled function when no `data` object + * is given, else it returns the interpolated text. + * @example + * + * // using a compiled template + * var compiled = _.template('hello <%= name %>'); + * compiled({ 'name': 'moe' }); + * // => 'hello moe' + * + * var list = '<% _.forEach(people, function(name) { %>
  • <%= name %>
    • <% }); %>'; + * _.template(list, { 'people': ['moe', 'larry', 'curly'] }); + * // => '
  • moe
  • larry
  • curly
    • ' + * + * // using the "escape" delimiter to escape HTML in data property values + * _.template('<%- value %>', { 'value': '