Files
lodash/lodash.js
2012-04-17 23:47:27 -04:00

2671 lines
78 KiB
JavaScript

/*!
* Lo-Dash v0.1.0 <https://github.com/bestiejs/lodash>
* Copyright 2012 John-David Dalton <http://allyoucanleet.com/>
* Based on Underscore.js 1.3.3, copyright 2009-2012 Jeremy Ashkenas, DocumentCloud Inc.
* <http://documentcloud.github.com/underscore>
* Available under MIT license <http://mths.be/mit>
*/
;(function(window, undefined) {
'use strict';
/** Used to assign each benchmark an incrimented id */
var idCounter = 0;
/** Detect free variable `exports` */
var freeExports = typeof exports == 'object' && exports &&
(typeof global == 'object' && global && global == global.global && (window = global), exports);
// Establish the object that gets returned to break out of a loop iteration.
var breaker = {};
var oldDash = window._;
// Save bytes in the minified (but not gzipped) version:
var ArrayProto = Array.prototype,
ObjProto = Object.prototype;
// Create quick reference variables for speed access to core prototypes.
var concat = ArrayProto.concat,
hasOwnProperty = ObjProto.hasOwnProperty,
push = ArrayProto.push,
slice = ArrayProto.slice,
toString = ObjProto.toString,
unshift = ArrayProto.unshift;
// All **ECMAScript 5** native function implementations that we hope to use
// are declared here.
var nativeIsArray = Array.isArray,
nativeIsFinite = window.isFinite,
nativeKeys = Object.keys;
// When customizing `templateSettings`, if you don't want to define an
// interpolation, evaluation or escaping regex, we need one that is
// guaranteed not to match.
var noMatch = /.^/;
// Certain characters need to be escaped so that they can be put into a
// string literal.
var escapes = {
'\\': '\\',
"'": "'",
'r': '\r',
'n': '\n',
't': '\t',
'u2028': '\u2028',
'u2029': '\u2029'
};
for (var p in escapes) escapes[escapes[p]] = p;
var escaper = /\\|'|\r|\n|\t|\u2028|\u2029/g;
var unescaper = /\\(\\|'|r|n|t|u2028|u2029)/g;
// Within an interpolation, evaluation, or escaping, remove HTML escaping
// that had been previously added.
var unescape = function(code) {
return code.replace(unescaper, function(match, escape) {
return escapes[escape];
});
};
/*--------------------------------------------------------------------------*/
/**
* The Lodash function.
*
* @name _
* @constructor
* @param {Mixed} value The value to wrap in a chainable `lowdash` object.
* @returns {Object} Returns a `lodash` instance.
* @example
*/
function lodash(value) {
// allow invoking `lodash` without the `new` operator
return new Wrapper(value);
}
/**
* Creates a wrapped collection that can be used OO-style. This wrapper holds
* altered versions of all the Lo-Dash functions. Wrapped objects may be chained.
*
* @private
* @constructor
* @param {Mixed} value The value to wrap in a chainable `lodash` object.
* @example
*/
function Wrapper(collection) {
this._wrapped = collection;
}
/*--------------------------------------------------------------------------*/
/**
* Internal recursive comparison function
*
* @private
* @param {Mixed} a A value.
* @param {Mixed} b Another value.
* @param {Array} stack Holds seen objects to avoid circular references.
* @example
*/
function eq(a, b, stack) {
// identical objects are equal. `0 === -0`, but they aren't identical
// See the Harmony `egal` proposal: http://wiki.ecmascript.org/doku.php?id=harmony:egal
if (a === b) {
return a !== 0 || (1 / a == 1 / b);
}
// a strict comparison is necessary because `null == undefined`
if (a == null || b == null) {
return a === b;
}
// unwrap any wrapped objects
if (a._chain) {
a = a._wrapped;
}
if (b._chain) {
b = b._wrapped;
}
// invoke a custom `isEqual` method if one is provided
if (a.isEqual && isFunction(a.isEqual)) {
return a.isEqual(b);
}
if (b.isEqual && isFunction(b.isEqual)) {
return b.isEqual(a);
}
// compare `[[Class]]` names
var className = toString.call(a);
if (className != toString.call(b)) {
return false;
}
switch (className) {
// strings, numbers, dates, and booleans are compared by value
case '[object String]':
// primitives and their corresponding collection wrappers are equivalent; thus, `"5"` is
// equivalent to `new String("5")`
return a == String(b);
case '[object Number]':
// `NaN`s are equivalent, but non-reflexive;
// an `egal` comparison is performed for other numeric values
return a != +a ? b != +b : (a == 0 ? 1 / a == 1 / b : a == +b);
case '[object Date]':
case '[object Boolean]':
// Coerce dates and booleans to numeric primitive values.
// Dates are compared by their millisecond representations.
// Note that invalid dates with millisecond representations of `NaN` are not equivalent.
return +a == +b;
// regexps are compared by their source and flags
case '[object RegExp]':
return a.source == b.source &&
a.global == b.global &&
a.multiline == b.multiline &&
a.ignoreCase == b.ignoreCase;
}
if (typeof a != 'object' || typeof b != 'object') {
return false;
}
// Assume equality for cyclic structures. The algorithm for detecting cyclic
// structures is adapted from ES 5.1 section 15.12.3, abstract operation `JO`.
var length = stack.length;
while (length--) {
// Linear search. Performance is inversely proportional to the number of
// unique nested structures.
if (stack[length] == a) {
return true;
}
}
// add the first collection to the stack of traversed objects
stack.push(a);
var size = 0, result = true;
// recursively compare objects and arrays
if (className == '[object Array]') {
// compare array 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--) {
// ensure commutative equality for sparse arrays
if (!(result = size in a == size in b && eq(a[size], b[size], stack))) {
break;
}
}
}
} else {
// objects with different constructors are not equivalent
if ('constructor' in a != 'constructor' in b || a.constructor != b.constructor) {
return false;
}
// deep compare objects
for (var key in a) {
if (hasOwnProperty.call(a, key)) {
// count the expected number of properties
size++;
// deep compare each member
if (!(result = hasOwnProperty.call(b, key) && eq(a[key], b[key], stack))) {
break;
}
}
}
// ensure that both objects contain the same number of properties
if (result) {
for (key in b) {
if (hasOwnProperty.call(b, key) && !(size--)) {
break;
}
}
result = !size;
}
}
// remove the first collection from the stack of traversed objects
stack.pop();
return result;
}
/*--------------------------------------------------------------------------*/
/**
* Checks if a given `target` value is present in a `collection` using strict
* equality for comparisons, i.e. `===`.
*
* @static
* @memberOf _
* @alias include
* @category Collections
* @param {Array|Object} collection The collection to iterate over.
* @param {Mixed} target The value to check for.
* @returns {Boolean} Returns `true` if `target` value is found, else `false`.
* @example
*
* _.contains([1, 2, 3], 3);
* // => true
*/
function contains(collection, target) {
return collection == null
? false
: some(collection, function(value) { return value === target; });
}
/**
* Checks if the `callback` returns truthy for **all** values of a `collection`.
* The `callback` is invoked with 3 arguments; for arrays they are
* (value, index, array) and for objects they are (value, key, object).
*
* @static
* @memberOf _
* @alias all
* @category Collections
* @param {Array|Object} collection The collection to iterate over.
* @param {Function} callback The function called per iteration.
* @param {Mixed} [thisArg] The `this` binding for the callback.
* @returns {Boolean} Returns `true` if all values pass the callback check, else `false`.
* @example
*
* _.every([true, 1, null, 'yes'], Boolean);
* => false
*/
function every(collection, callback, thisArg) {
var result = true;
if (collection == null) return result;
forEach(collection, function(value, index, array) {
if (!(result = result && callback.call(thisArg, value, index, array))) return breaker;
});
return !!result;
}
/**
* Examines each value in a `collection`, returning an array of all values the
* `callback` returns truthy for. The `callback` is invoked with 3 arguments;
* for arrays they are (value, index, array) and for objects they are
* (value, key, object).
*
* @static
* @memberOf _
* @alias select
* @category Collections
* @param {Array|Object} collection The collection to iterate over.
* @param {Function} callback The function called per iteration.
* @param {Mixed} [thisArg] The `this` binding for the callback.
* @returns {Array} Returns a new array of values that passed 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 = [];
if (collection == null) return result;
forEach(collection, function(value, index, array) {
if (callback.call(thisArg, value, index, array)) result[result.length] = value;
});
return result;
}
/**
* Examines each value in a `collection`, returning the first one the `callback`
* returns truthy for. The function returns as soon as it finds an acceptable
* value, and does not iterate over the entire `collection`. The `callback` is
* invoked with 3 arguments; for arrays they are (value, index, array) and for
* objects they are (value, key, object).
*
* @static
* @memberOf _
* @alias detect
* @category Collections
* @param {Array|Object} collection The collection to iterate over.
* @param {Function} callback The function called per iteration.
* @param {Mixed} [thisArg] The `this` binding for the callback.
* @returns {Mixed} Returns the value that passed the callback check.
* @example
*
* var even = _.find([1, 2, 3, 4, 5, 6], function(num) { return num % 2 == 0; });
* // => 2
*/
function find(collection, callback, thisArg) {
var result;
some(collection, function(value, index, array) {
if (callback.call(thisArg, value, index, array)) {
result = value;
return true;
}
});
return result;
}
/**
* Iterates over a `collection`, executing the `callback` for each value in the
* `collection`. The `callback` is bound to the `thisArg` value, if one is passed.
* The `callback` is invoked with 3 arguments; for arrays they are
* (value, index, array) and for objects they are (value, key, object).
*
* @static
* @memberOf _
* @alias each
* @category Collections
* @param {Array|Object} collection The collection to iterate over.
* @param {Function} callback The function called per iteration.
* @param {Mixed} [thisArg] The `this` binding for the callback.
* @returns {Array|Object} Returns the `collection`.
* @example
*
* _.forforEach([1, 2, 3], function(num) { alert(num); });
* // => alerts each number in turn...
*
* _.forforEach({ 'one': 1, 'two': 2, 'three': 3}, function(num) { alert(num); });
* // => alerts each number in turn...
*/
function forEach(collection, callback, thisArg) {
if (collection != null) {
if (collection.length === +collection.length) {
for (var index = 0, length = collection.length; index < length; index++) {
if (index in collection && callback.call(thisArg, collection[index], index, collection) === breaker) {
break;
}
}
} else {
for (var key in collection) {
if (hasOwnProperty.call(collection, key)) {
if (callback.call(thisArg, collection[key], key, collection) === breaker) {
break;
}
}
}
}
}
return collection;
}
/**
* Splits a `collection` into sets, grouped by the result of running each value
* through `callback`. The `callback` is invoked with 3 arguments; for arrays
* they are (value, index, array) and for objects they are (value, key, object).
* The `callback` argument may also be the name of a property to group by.
*
* @static
* @memberOf _
* @category Collections
* @param {Array|Object} collection The collection to iterate over.
* @param {Function|String} callback The function called per iteration or
* property name to group by.
* @param {Mixed} [thisArg] The `this` binding for the callback.
* @returns {Object} Returns an object of grouped values.
* @example
*
* _.groupBy([1.3, 2.1, 2.4], function(num) { return Math.floor(num); });
* // => { '1': [1.3], '2': [2.1, 2.4] }
*
* _.groupBy(['one', 'two', 'three'], 'length');
* // => { '3': ['one', 'two'], '5': ['three'] }
*/
function groupBy(collection, callback, thisArg) {
var result = {};
if (!isFunction(callback)) {
var key = callback;
callback = function(collection) { return collection[key]; };
}
forEach(collection, function(value, index) {
var key = callback(value, index);
(result[key] || (result[key] = [])).push(value);
});
return result;
}
/**
* Calls the method named by `methodName` for each value of the `collection`.
* Additional arguments will be passed to each invoked method.
*
* @static
* @memberOf _
* @category Collections
* @param {Array|Object} collection The collection to iterate over.
* @param {String} methodName The name of the method to invoke.
* @param {Mixed} [arg1, arg2, ...] Arguments to invoke the method with.
* @returns {Array} Returns a new array of values returned from each invoked method.
* @example
*
* _.invoke([[5, 1, 7], [3, 2, 1]], 'sort');
* // => [[1, 5, 7], [1, 2, 3]]
*/
function invoke(collection, methodName) {
var args = slice.call(arguments, 2),
isFunc = isFunction(methodName);
return map(collection, function(value) {
return (isFunc ? methodName || value : value[methodName]).apply(value, args);
});
}
/**
* Produces a new array of values by mapping each value in the `collection`
* through a transformation `callback`. The `callback` is bound to the `thisArg`
* value, if one is passed. The `callback` is invoked with 3 arguments; for
* arrays they are (value, index, array) and for objects they are (value, key, object).
*
* @static
* @memberOf _
* @alias collect
* @category Collections
* @param {Array|Object} collection The collection to iterate over.
* @param {Function} callback The function called per iteration.
* @param {Mixed} [thisArg] The `this` binding for the callback.
* @returns {Array} Returns a new array of values returned by the callback.
* @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]
*/
function map(collection, callback, thisArg) {
var result = [];
if (collection == null) {
return result;
}
forEach(collection, function(value, index, array) {
result[result.length] = callback.call(thisArg, value, index, array);
});
if (collection.length === +collection.length) result.length = collection.length;
return result;
}
/**
* Retrieves the maximum value of a `collection`. If `callback` is passed,
* it will be executed for each value in the `collection` to generate the
* criterion by which the value is ranked. The `callback` is invoked with 3
* arguments; for arrays they are (value, index, array) and for objects they
* are (value, key, object).
*
* @static
* @memberOf _
* @category Collections
* @param {Array|Object} collection The collection to iterate over.
* @param {Function} [callback] The function called per iteration.
* @param {Mixed} [thisArg] The `this` binding for the 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) {
if (!callback) {
if (isArray(collection) && collection[0] === +collection[0]) {
return Math.max.apply(Math, collection);
}
if (isEmpty(collection)) {
return -Infinity;
}
} else if (thisArg) {
callback = bind(callback, thisArg);
}
var result = { 'computed': -Infinity };
forEach(collection, function(value, index, array) {
var computed = callback ? callback(value, index, array) : value;
if (computed >= result.computed) {
result = { 'computed': computed, 'value': value };
}
});
return result.value;
}
/**
* Retrieves the minimum value of a `collection`. If `callback` is passed,
* it will be executed for each value in the `collection` to generate the
* criterion by which the value is ranked. The `callback` is invoked with 3
* arguments; for arrays they are (value, index, array) and for objects they
* are (value, key, object).
*
* @static
* @memberOf _
* @category Collections
* @param {Array|Object} collection The collection to iterate over.
* @param {Function} [callback] The function called per iteration.
* @param {Mixed} [thisArg] The `this` binding for the callback.
* @returns {Mixed} Returns the minimum value.
* @example
*
* _.min([10, 5, 100, 2, 1000]);
* // => 2
*/
function min(collection, callback, thisArg) {
if (!callback) {
if (isArray(collection) && collection[0] === +collection[0]) {
return Math.min.apply(Math, collection);
}
if (isEmpty(collection)) {
return Infinity;
}
} else if (thisArg) {
callback = bind(callback, thisArg);
}
var result = { 'computed': Infinity };
forEach(collection, function(value, index, array) {
var computed = callback ? callback(value, index, array) : value;
if (computed < result.computed) {
result = { 'computed': computed, 'value': value };
}
});
return result.value;
}
/**
* Retrieves the value of a specified property from all values in a `collection`.
*
* @static
* @memberOf _
* @category Collections
* @param {Array|Object} 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, key) {
return map(collection, function(value) { return value[key]; });
}
/**
* 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 the `thisArg` value, if one is
* passed. The `callback` is invoked with 4 arguments; for arrays they are
* (accumulator, value, index, array) and for objects they are
* (accumulator, value, key, object).
*
* @static
* @memberOf _
* @alias foldl, inject
* @category Collections
* @param {Array|Object} 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 for the 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 initial = arguments.length > 2;
if (thisArg) {
callback = bind(callback, thisArg);
}
forEach(collection, function(value, index) {
if (!initial) {
accumulator = value;
initial = true;
} else {
accumulator = callback(accumulator, value, index, collection);
}
});
return accumulator;
}
/**
* The right-associative version of `_.reduce`. The `callback` is bound to the
* `thisArg` value, if one is passed. The `callback` is invoked with 4 arguments;
* for arrays they are (accumulator, value, index, array) and for objects they
* are (accumulator, value, key, object).
*
* @static
* @memberOf _
* @alias foldr
* @category Collections
* @param {Array|Object} 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 for the 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 initial = arguments.length > 2,
reversed = toArray(collection).reverse();
return initial ? reduce(reversed, callback, accumulator, thisArg) : reduce(reversed, callback);
}
/**
* The opposite of `_.filter`, this method returns the values of a `collection`
* that `callback` does **not** return truthy for. The `callback` is invoked
* with 3 arguments; for arrays they are (value, index, array) and for objects
* they are (value, key, object).
*
* @static
* @memberOf _
* @category Collections
* @param {Array|Object} collection The collection to iterate over.
* @param {Function} callback The function called per iteration.
* @param {Mixed} [thisArg] The `this` binding for the callback.
* @returns {Array} Returns a new array of values 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) {
var result = [];
if (collection == null) return result;
forEach(collection, function(value, index, array) {
if (!callback.call(thisArg, value, index, array)) result[result.length] = value;
});
return result;
}
/**
* Produces a new array of shuffled `collection` 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} collection The collection to shuffle.
* @returns {Array} Returns a new shuffled array.
* @example
*
* _.shuffle([1, 2, 3, 4, 5, 6]);
* // => [4, 1, 6, 3, 5, 2]
*/
function shuffle(collection) {
var rand,
result = [];
forEach(collection, function(value, index, array) {
rand = Math.floor(Math.random() * (index + 1));
result[index] = result[rand];
result[rand] = value;
});
return result;
}
/**
* Gets the number of values in the `collection`.
*
* @static
* @memberOf _
* @category Collections
* @param {Array|Object} collection The collection inspect.
* @returns {Number} Returns the number of values in the collection.
* @example
*
* _.size({ 'one': 1, 'two': 2, 'three': 3 });
* // => 3
*/
function size(collection) {
return isArray(collection) ? collection.length : keys(collection).length;
}
/**
* Produces a new sorted array, ranked in ascending order by the results of
* running each value of a `collection` through `callback`. The `callback` is
* invoked with 3 arguments; for arrays they are (value, index, array) and for
* objects they are (value, key, object). The `callback` argument may also be
* the name of a property to sort by (e.g. 'length').
*
* @static
* @memberOf _
* @category Collections
* @param {Array|Object} collection The collection to iterate over.
* @param {Function|String} callback The function called per iteration or
* property name to sort by.
* @param {Mixed} [thisArg] The `this` binding for the callback.
* @returns {Array} Returns a new array of sorted values.
* @example
*
* _.sortBy([1, 2, 3, 4, 5, 6], function(num) { return Math.sin(num); });
* // => [5, 4, 6, 3, 1, 2]
*/
function sortBy(collection, callback, thisArg) {
if (!isFunction(callback)) {
var key = callback;
callback = function(collection) { return collection[key]; };
} else if (thisArg) {
callback = bind(callback, thisArg);
}
return pluck(map(collection, function(value, index) {
return {
'criteria': callback(value, index, collection),
'value': value
};
}).sort(function(left, right) {
var a = left.criteria,
b = right.criteria;
if (a === undefined) {
return 1;
}
if (b === undefined) {
return -1;
}
return a < b ? -1 : a > b ? 1 : 0;
}), 'value');
}
/**
* Checks if the `callback` returns truthy for **any** value of a `collection`.
* The function returns as soon as it finds passing value, and does not iterate
* over the entire `collection`. The `callback` is invoked with 3 arguments; for
* arrays they are (value, index, array) and for objects they are
* (value, key, object).
*
* @static
* @memberOf _
* @alias any
* @category Collections
* @param {Array|Object} collection The collection to iterate over.
* @param {Function} callback The function called per iteration.
* @param {Mixed} [thisArg] The `this` binding for the callback.
* @returns {Boolean} Returns `true` if any value passes the callback check, else `false`.
* @example
*
* _.some([null, 0, 'yes', false]);
* // => true
*/
function some(collection, callback, thisArg) {
var result = false;
if (!callback) {
callback = identity;
} else if (thisArg) {
callback = bind(callback, thisArg);
}
if (collection == null) return result;
forEach(collection, function(value, index, array) {
if (result || (result = callback.call(thisArg, value, index, array))) return breaker;
});
return !!result;
}
/**
* Uses a binary search to determine the index at which the `value` should be
* inserted into the `collection` in order to maintain the `collection`'s sorted
* order. If `callback` is passed, it will be executed for each value in the
* `collection` to compute their sort ranking. The `callback` is invoked with
* 1 arguments.
*
* @static
* @memberOf _
* @category Collections
* @param {Array} array The array to iterate over.
* @param {Mixed} value The value to evaluate.
* @param {Function} [callback] The function called per iteration.
* @returns {Number} Returns the index at which the value should be inserted
* into the collection.
* @example
*
* _.sortedIndex([10, 20, 30, 40, 50], 35);
* // => 3
*/
function sortedIndex(array, object, callback) {
var low = 0,
high = array.length;
callback || (callback = identity);
while (low < high) {
var mid = (low + high) >> 1;
callback(array[mid]) < callback(object) ? (low = mid + 1) : (high = mid);
}
return low;
}
/**
* Converts the `collection`, into an array. Useful for converting the
* `arguments` object.
*
* @static
* @memberOf _
* @category Collections
* @param {Array|Object} 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) {
return [];
}
if (isArray(collection) || isArguments(collection)) {
return slice.call(collection);
}
if (isFunction(collection.toArray)) {
return collection.toArray();
}
return values(collection);
}
/*--------------------------------------------------------------------------*/
/**
* Produces a new 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) {
return filter(array, Boolean);
}
/**
* Produces a new array of `array` values 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 {Mixed} [array1, array2, ...] Arrays to check.
* @returns {Array} Returns a new array of `array` values not present in the
* other arrays.
* @example
*
* _.difference([1, 2, 3, 4, 5], [5, 2, 10]);
* // => [1, 3, 4]
*/
function difference(array) {
var values = concat.apply([], slice.call(arguments, 1));
return filter(array, function(value) { return indexOf(values, value) < 0; });
}
/**
* Gets the first value of the `array`. Pass `n` to return the first `n` values
* 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] Used to allow the function to work with other iteration
* methods like `_.map` without using their callback `index` argument for `n`.
* @returns {Mixed} Returns the first value or an array of the first `n`
* values of the `array`.
* @example
*
* _.first([5, 4, 3, 2, 1]);
* // => 5
*/
function first(array, n, guard) {
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) {
if (shallow) {
return concat.apply([], array);
}
return reduce(array, function(accumulator, value) {
if (isArray(value)) {
push.apply(accumulator, flatten(value));
return accumulator;
}
accumulator.push(value);
return accumulator;
}, []);
}
/**
* 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 `isSorted` 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} [isSorted=false] A flag to indicate that the `array` is already sorted.
* @returns {Number} Returns the index of the matched value or `-1`.
* @example
*
* _.indexOf([1, 2, 3], 2);
* // => 1
*/
function indexOf(array, value, isSorted) {
var index, length;
if (array == null) {
return -1;
}
if (isSorted) {
index = sortedIndex(array, value);
return array[index] === value ? index : -1;
}
for (index = 0, length = array.length; index < length; index++) {
if (array[index] === value) {
return index;
}
}
return -1;
}
/**
* Gets all but the last value of the `array`. Pass `n` to exclude the last `n`
* values from the result.
*
* @static
* @memberOf _
* @category Arrays
* @param {Array} array The array to query.
* @param {Number} [n] The number of elements to return.
* @param {Object} [guard] Used to allow the function to work with other iteration
* methods like `_.map` without using their callback `index` argument for `n`.
* @returns {Array} Returns all but the last value or `n` values of the `array`.
* @example
*
* _.initial([5, 4, 3, 2, 1]);
* // => [5, 4, 3, 2]
*/
function initial(array, n, guard) {
return slice.call(array, 0, -((n == null || guard) ? 1 : n));
}
/**
* Computes the intersection of all the passed-in arrays.
*
* @static
* @memberOf _
* @alias intersect
* @category Arrays
* @param {Mixed} [array1, array2, ...] Arrays to process.
* @returns {Array} Returns a new array of unique values, 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 rest = slice.call(arguments, 1);
return filter(uniq(array), function(value) {
return every(rest, function(other) {
return indexOf(other, value) >= 0;
});
});
}
/**
* Gets the last value of the `array`. Pass `n` to return the lasy `n` values
* 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] Used to allow the function to work with other iteration
* methods like `_.map` without using their callback `index` argument for `n`.
* @returns {Array} Returns all but the last value or `n` values of the `array`.
* @example
*
* _.last([5, 4, 3, 2, 1]);
* // => 1
*/
function last(array, n, guard) {
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. `===`.
*
* @static
* @memberOf _
* @category Arrays
* @param {Array} array The array to search.
* @param {Mixed} value The value to search for.
* @returns {Number} Returns the index of the matched value or `-1`.
* @example
*
* _.lastIndexOf([1, 2, 3, 1, 2, 3], 2);
* // => 4
*/
function lastIndexOf(array, value) {
if (array == null) {
return -1;
}
var index = array.length;
while (index--) {
if (array[index] === value) {
return index;
}
}
return -1;
}
/**
* 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) {
step || (step = 1);
if (arguments.length < 2) {
end = start || 0;
start = 0;
}
var idx = 0,
length = Math.max(Math.ceil((end - start) / step), 0),
result = Array(length);
while (idx < length) {
result[idx++] = start;
start += step;
}
return result;
}
/**
* The opposite of `_.initial`, this method gets all but the first value of
* the `array`. Pass `n` to exclude the first `n` values from the result.
*
* @static
* @memberOf _
* @alias tail
* @category Arrays
* @param {Array} array The array to query.
* @param {Number} [n] The number of elements to return.
* @param {Object} [guard] Used to allow the function to work with other iteration
* methods like `_.map` without using their callback `index` argument for `n`.
* @returns {Array} Returns all but the first value or `n` values of the `array`.
* @example
*
* _.rest([5, 4, 3, 2, 1]);
* // => [4, 3, 2, 1]
*/
function rest(array, index, guard) {
return slice.call(array, (index == null || guard) ? 1 : index);
}
/**
* Computes the union of the passed-in arrays.
*
* @static
* @memberOf _
* @category Arrays
* @param {Mixed} [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(flatten(arguments, true));
}
/**
* Produces 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 value of `array` is passed through a transformation `callback` before
* uniqueness is computed. The `callback` is invoked with 3 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] A
* @returns {Array} Returns a duplicate-value-free array.
* @example
*
* _.uniq([1, 2, 1, 3, 1, 4]);
* // => [1, 2, 3, 4]
*/
function uniq(array, isSorted, callback) {
var initial = callback ? map(array, callback) : array,
result = [];
// the `isSorted` flag is irrelevant if the array only contains two elements.
if (array.length < 3) {
isSorted = true;
}
reduce(initial, function(accumulator, value, index) {
if (isSorted ? last(accumulator) !== value || !accumulator.length : indexOf(accumulator, value) < 0) {
accumulator.push(value);
result.push(array[index]);
}
return accumulator;
}, []);
return result;
}
/**
* Produces a new array with all occurrences of the 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) {
return difference(array, slice.call(arguments, 1));
}
/**
* Merges together the values of each of the arrays with the value at the
* corresponding position. 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 {Mixed} [array1, array2, ...] Arrays to process.
* @returns {Array} Returns a new array of merged arrays.
* @example
*
* _.zip(['moe', 'larry', 'curly'], [30, 40, 50], [true, false, false]);
* // => [['moe', 30, true], ['larry', 40, false], ['curly', 50, false]]
*/
function zip() {
var index = -1,
length = max(pluck(arguments, 'length')),
result = Array(length);
while (++index < length) {
result[index] = pluck(arguments, index);
}
return result;
}
/*--------------------------------------------------------------------------*/
/**
* Creates a new function that is restricted to executing only after it is
* called a given number of `times`.
*
* @static
* @memberOf _
* @category Functions
* @param {Number} times 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(times, func) {
if (times < 1) {
return func();
}
return function() {
if (--times < 1) {
return func.apply(this, arguments);
}
};
}
/**
* Creates a new function that, when called, invokes `func` with the `this`
* binding of `thisArg` and prepends additional arguments to those passed to
* the bound function.
*
* @static
* @memberOf _
* @category Functions
* @param {Function} func The function to bind.
* @param @param {Mixed} [thisArg] The `this` binding of `func`.
* @param {Mixed} [arg1, arg2, ...] Arguments to prepend to those passed to the bound function.
* @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) {
var args = slice.call(arguments, 2),
argsLength = args.length;
return function() {
args.length = argsLength;
push.apply(args, arguments);
return func.apply(thisArg, args);
};
}
/**
* Binds methods on the `object` to the object, overwriting the non-bound method.
* If no method names are provided, all the function properties of the `object`
* will be bound.
*
* @static
* @memberOf _
* @category Functions
* @param {Object} object The object to bind and assign the bound methods to.
* @param {Mixed} [methodName1, methodName2, ...] Method names on the object to bind.
* @returns {Object} Returns the `object`.
* @example
*
* var buttonView = {
* 'label': 'lodash',
* 'onClick': function() { alert('clicked: ' + this.label); },
* 'onHover': function() { console.log('hovering: ' + 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 = slice.call(arguments, 1);
if (!funcs.length) {
funcs = functions(object);
}
forEach(funcs, function(methodName) {
object[methodName] = bind(object[methodName], object);
});
return object;
}
/**
* Creates a new 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 thefunctions `f()`, `g()`, and `h()` produces `f(g(h()))`.
*
* @static
* @memberOf _
* @category Functions
* @param {Mixed} [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;
for (var index = funcs.length - 1; index >= 0; index--) {
args = [funcs[index].apply(this, args)];
}
return args[0];
};
}
/**
* Creates a new function that will postpone its execution until after `wait`
* milliseconds have elapsed since the last time it was invoked. Pass `true`
* for `immediate` to cause debounce to invoke the function on the leading,
* intead of the trailing, edge of the wait timeout.
*
* @static
* @memberOf _
* @category Functions
* @param {Function} func The function to debounce.
* @param {Number} wait The number of milliseconds to postone.
* @param {Boolean} immediate A flag to indicate execution is on the leading
* edge of the wait 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 timeout;
return function() {
var args = arguments,
thisArg = this;
if (immediate && !timeout) {
func.apply(thisArg, args);
}
clearTimeout(timeout);
timeout = setTimeout(function() {
timeout = null;
if (!immediate) {
func.apply(thisArg, args);
}
}, wait);
};
}
/**
* Invokes the `func` function after `wait` milliseconds. Additional arguments
* are passed `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() { return func.apply(null, args); }, wait);
}
/**
* Defers invoking the `func` function until the current call stack has cleared.
* Additional arguments are 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 the alert runs.
*/
function defer(func) {
var args = [func, 1];
push.apply(args, slice.call(arguments, 1));
return delay.apply(lodash, args);
}
/**
* Creates a new function that memoizes the result of `func`. If `hasher` is
* passed, it will be used to compute the hash key for storing the result,
* based on the arguments to the original function. The default `hasher` uses
* the first argument to the memoized function as the cache key.
*
* @static
* @memberOf _
* @category Functions
* @param {Function} func The function to memoize the output of.
* @param {Function} [hasher=_.identity] A function used to resolve the cache keyW.
* @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, hasher) {
var cache = {};
hasher || (hasher = identity);
return function() {
var key = hasher.apply(this, arguments);
return hasOwnProperty.call(cache, key)
? cache[key]
: (cache[key] = func.apply(this, arguments));
};
}
/**
* Creates a new function that is restricted to one execution. Repeat calls to
* the function will return the value of the first call.
*
* @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);
return result;
};
}
/**
* Creates a new function that, when invoked, will only call the original
* function at most once per every `wait` milliseconds.
*
* @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, more, result, thisArg, throttling, timeout,
whenDone = debounce(function() { more = throttling = false; }, wait);
return function() {
args = arguments;
thisArg = this;
if (!timeout) {
timeout = setTimeout(function() {
timeout = null;
if (more) {
func.apply(thisArg, args);
}
whenDone();
}, wait);
}
if (throttling) {
more = true;
} else {
result = func.apply(thisArg, args);
}
whenDone();
throttling = true;
return result;
};
}
/**
* Create a new function that passes the `func` function to the `wrapper`
* function as its first argument. Additional arguments are appended to those
* passed to the `wrapper` function.
*
* @static
* @memberOf _
* @category Functions
* @param {Function} func The function to wrap.
* @param {Function} wrapper The wrapper function.
* @param {Mixed} [arg1, arg2, ...] Arguments to append to those passed to the wrapper.
* @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(func, wrapper) {
return function() {
var args = [func];
push.apply(args, arguments);
return wrapper.apply(this, args);
};
}
/*--------------------------------------------------------------------------*/
/**
* Create a shallow clone of the `value`. Any nested objects or arrays will be
* assigned by reference and not cloned.
*
* @static
* @memberOf _
* @category Objects
* @param {Mixed} value The value to clone.
* @returns {Mixed} Returns the cloned `value`.
* @example
*
* _.clone({ 'name': 'moe' });
* // => { 'name': 'moe' };
*/
function clone(value) {
if (!isObject(value)) {
return value;
}
return isArray(value) ? value.slice() : extend({}, value);
}
/**
* Assigns missing properties in `object` with default values from the defaults
* objects. As soon as a property is set, additional defaults of the same
* property will be ignored.
*
* @static
* @memberOf _
* @category Objects
* @param {Object} object The object to populate.
* @param {Object} [defaults1, defaults2, ..] The defaults objects to apply to `object`.
* @returns {Object} Returns `object`.
* @example
*
* var iceCream = { 'flavor': 'chocolate' };
* _.defaults(iceCream, { 'flavor': 'vanilla', 'sprinkles': 'lots' });
* // => { 'flavor': 'chocolate', 'sprinkles': 'lots' }
*/
function defaults(object) {
forEach(slice.call(arguments, 1), function(source) {
for (var prop in source) {
if (object[prop] == null) object[prop] = source[prop];
}
});
return object;
}
/**
* Copies enumerable properties from the source objects to the `destination` object.
* Subsequent sources will overwrite propery assignments of previous sources.
*
* @static
* @memberOf _
* @category Objects
* @param {Object} destination 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 }
*/
function extend(destination) {
forEach(slice.call(arguments, 1), function(source) {
for (var prop in source) {
destination[prop] = source[prop];
}
});
return destination;
}
/**
* Produces a sorted array of the `object`'s enumerable own property names 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 names = [];
for (var key in object) {
if (isFunction(object[key])) {
names.push(key);
}
}
return names.sort();
}
/**
* Checks if an object has the specified key as a direct property.
*
* @static
* @memberOf _
* @category Objects
* @param {Object} object The object to check.
* @param {String} key The key 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, key) {
return hasOwnProperty.call(object, key);
}
/**
* Checks if a `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) == '[object Arguments]';
}
/**
* Checks if a `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
*/
function isArray(value) {
return toString.call(value) == '[object Array]';
}
/**
* Checks if a `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) == '[object Boolean]';
}
/**
* Checks if a `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) == '[object Date]';
}
/**
* Checks if a `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);
}
/**
* Checks if a `value` is empty. Arrays or strings with a length of 0 and
* objects with no enumerable own properties are considered "empty".
*
* @static
* @memberOf _
* @category Objects
* @param {Mixed} value The value to check.
* @returns {Boolean} Returns `true` if the `value` is empty, else `false`.
* @example
*
* _.isEmpty([1, 2, 3]);
* // => false
*
* _.isEmpty({});
* // => true
*/
function isEmpty(value) {
if (value == null) {
return true;
}
if (isArray(value) || isString(value)) {
return value.length === 0;
}
for (var key in value) {
if (hasOwnProperty.call(value, key)) {
return false;
}
}
return true;
}
/**
* Performs a deep comparison between two values to determine if they are
* equivalent to each other.
*
* @static
* @memberOf _
* @category Objects
* @param {Mixed} value The value to compare.
* @param {Mixed} other The other value to compare.
* @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(value, other) {
return eq(value, other, []);
}
/**
* Checks if a `value` is a finite number.
*
* @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');
* // => false
*
* _.isFinite(Infinity);
* // => false
*/
function isFinite(value) {
return isNumber(value) && nativeIsFinite(value);
}
/**
* Checks if a `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(''.concat);
* // => true
*/
function isFunction(value) {
return toString.call(value) == '[object Function]';
}
/**
* Checks if a `value` is an object.
*
* @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);
* // => false
*/
function isObject(value) {
return value === Object(value);
}
/**
* Checks if a `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.
*
* @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(undefined);
* // => true
*
* _.isNaN(undefined);
* // => false
*/
function isNaN(value) {
// `NaN` is the only value for which `===` is not reflexive.
return value !== value;
}
/**
* Checks if a `value` is `null`.
*
* @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 a `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) == '[object Number]';
}
/**
* Checks if a `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) == '[object RegExp]';
}
/**
* Checks if a `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) == '[object String]';
}
/**
* Checks if a `value` is `undefined`.
*
* @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 === void 0;
}
/**
* Produces an array of the `object`'s enumerable own property names.
*
* @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']
*/
function keys(object) {
if (object !== Object(object)) {
throw TypeError();
}
var result = [];
for (var key in object) {
if (hasOwnProperty.call(object, key)) {
result.push(key);
}
}
return result;
}
/**
* Creates an object composed of the specified properties. Property names may
* be specified as individual arguments or as arrays of property names.
*
* @static
* @memberOf _
* @category Objects
* @param {Object} object The object to pluck.
* @param {Object} [prop1, prop2, ..] The properties to pick.
* @returns {Object} Returns an object composed of the picked properties.
* @example
*
* _.pick({ 'name': 'moe', 'age': 40, 'userid': 'moe1' }, 'name', 'age');
* // => { 'name': 'moe', 'age': 40 }
*/
function pick(object) {
var result = {};
forEach(flatten(slice.call(arguments, 1)), function(key) {
if (key in object) {
result[key] = object[key];
}
});
return result;
}
/**
* Invokes `interceptor` with the `value` as the first argument, and then returns
* `value`. The primary purpose of this method is to "tap into" a method chain,
* in order to performoperations on intermediate results within the chain.
*
* @static
* @memberOf _
* @category Objects
* @param {Mixed} value The value to pass to `callback`.
* @param {Function} interceptor The function to invoke.
* @returns {Mixed} Returns `value`.
* @example
*
* _.chain([1,2,3,200])
* .filter(function(num) { return num % 2 == 0; })
* .tap(alert)
* .map(function(num) { return num * num })
* .value();
* // => // [2, 200] (alerted)
* // => [4, 40000]
*/
function tap(value, interceptor) {
interceptor(value);
return value;
}
/**
* Produces an array of the `object`'s enumerable own property values.
*
* @static
* @memberOf _
* @alias methods
* @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) {
return map(object, identity);
}
/*--------------------------------------------------------------------------*/
/**
* Escapes a string for insertion into HTML, replacing `&`, `<`, `>`, `"`, `'`,
* and `/` characters.
*
* @static
* @memberOf _
* @category Utilities
* @param {String} string The string to escape.
* @returns {String} Returns the escaped string.
* @example
*
* _.escape('Curly, Larry & Moe');
* // => "Curly, Larry &amp; Moe"
*/
function escape(string) {
return (string + '')
.replace(/&/g, '&amp;').replace(/</g, '&lt;')
.replace(/>/g, '&gt;').replace(/"/g, '&quot;')
.replace(/'/g, '&#x27;').replace(/\//g,'&#x2F;');
}
/**
* This function simply returns the first argument passed to it.
* Note: It is used throughout Lodash 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('curly');
* // => 'Curly'
*
* _('larry').capitalize();
* // => 'Larry'
*/
function mixin(object) {
forEach(functions(object), function(methodName) {
var func = lodash[methodName] = object[methodName];
lodash.prototype[methodName] = function() {
// In Opera < 9.50 and some older/beta Mobile Safari versions using `unshift()`
// generically to augment the `arguments` object will pave the value at
// index `0` without incrimenting the other values's indexes.
// https://github.com/documentcloud/underscore/issues/9
var args = slice.call(arguments);
unshift.call(args, this._wrapped);
var result = func.apply(lodash, args);
return this._chain ? lodash(result).chain() : 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;
}
/**
* Resolves the value of `property` on `object`. If the property is a function
* it will be invoked and its result returned, else the property value is returned.
*
* @static
* @memberOf _
* @category Utilities
* @param {Object} object The object to inspect.
* @param {String} property The property to get the result of.
* @returns {Mixed} Returns the resolved.
* @example
*
* var object = {
* 'cheese': 'crumpets',
* 'stuff': function() {
* return 'nonsense';
* }
* };
*
* _.result(object, 'cheese');
* // => 'crumpets'
*
* _.result(object, 'stuff');
* // => 'nonsense'
*/
function result(object, property) {
if (object == null) {
return null;
}
var value = object[property];
return isFunction(value) ? object[property]() : value;
}
/**
* Executes the `callback` function `n` times.
*
* @static
* @memberOf _
* @category Utilities
* @param {Number} n The number of times to execute the callback.
* @param {Function} callback The function called per iteration.
* @param {Mixed} [thisArg] The `this` binding for the callback.
* @example
*
* _.times(3, function() { genie.grantWish(); });
*/
function times(n, callback, thisArg) {
if (thisArg) {
callback = bind(callback, thisArg);
}
for (var index = 0; index < n; index++) {
callback(index);
}
}
/**
* Generates a unique id. If `prefix` is passed, the id will be appended to it.
*
* @static
* @memberOf _
* @category Utilities
* @param {String} [prefix] The value to prefix the id with.
* @returns {Number|String} Returns a numeric id if no prefix is passed, else
* a string id may be returned.
* @example
*
* _.uniqueId('contact_');
* // => 'contact_104'
*/
function uniqueId(prefix) {
var id = idCounter++;
return prefix ? prefix + id : id;
}
/*--------------------------------------------------------------------------*/
/**
* JavaScript micro-templating, similar to John Resig's implementation.
* Lo-Dash templating handles arbitrary delimiters, preserves whitespace,
* and correctly escapes quotes within interpolated code.
*
* @static
* @memberOf _
* @category Utilities
* @param {String} text The
* @param {Obect} data The
* @param {Object} settings
* @returns {String} Returns....
* @example
*
* var compiled = _.template('hello: <%= name %>');
* compiled({ 'name': 'moe' });
* // => 'hello: moe'
*
* var list = '% _.forEach(people, function(name) { %> <li><%= name %></li> <% }); %>';
* _.template(list, { 'people': ['moe', 'curly', 'larry'] });
* // => '<li>moe</li><li>curly</li><li>larry</li>'
*
* var template = _.template('<b><%- value %></b>');
* template({ 'value': '<script>' });
* // => '<b>&lt;script&gt;</b>'
*
*
* var compiled = _.template('<% print("Hello " + epithet); %>');
* compiled({ 'epithet': 'stooge' });
* // => 'Hello stooge.'
*
*
* _.templateSettings = {
* 'interpolate': /\{\{(.+?)\}\}/g
* };
*
* var template = _.template('Hello {{ name }}!');
* template({ 'name': 'Mustache' });
* // => 'Hello Mustache!'
*
*
* _.template('<%= data.hasWith %>', { 'hasWith': 'no' }, { 'variable': 'data' });
* // => 'no'
*
*
* <script>
* JST.project = <%= _.template(jstText).source %>;
* </script>
*/
function template(text, data, settings) {
settings = defaults(settings || {}, lodash.templateSettings);
// Compile the template source, taking care to escape characters that
// cannot be included in a string literal and then unescape them in code
// blocks.
var source = "__p+='" + text
.replace(escaper, function(match) {
return '\\' + escapes[match];
})
.replace(settings.escape || noMatch, function(match, code) {
return "'+\n_.escape(" + unescape(code) + ")+\n'";
})
.replace(settings.interpolate || noMatch, function(match, code) {
return "'+\n(" + unescape(code) + ")+\n'";
})
.replace(settings.evaluate || noMatch, function(match, code) {
return "';\n" + unescape(code) + "\n;__p+='";
}) + "';\n";
// If a variable is not specified, place data values in local scope.
if (!settings.variable) {
source = 'with(object||{}){\n' + source + '}\n';
}
source = "var __p='';" +
"var print=function(){__p+=Array.prototype.join.call(arguments, '')};\n" +
source + "return __p;\n";
var render = Function(settings.variable || 'object', '_', source);
if (data) {
return render(data, lodash);
}
var template = function(data) {
return render.call(this, data, lodash);
};
// Provide the compiled function source as a convenience for build time
// precompilation.
template.source = 'function(' + (settings.variable || 'object') + '){\n' +
source + '}';
return template;
}
/*--------------------------------------------------------------------------*/
/**
* Wraps the value in a `lodash` chainable object.
*
* @static
* @memberOf _
* @category Chaining
* @param {Mixed} value The value to wrap.
* @returns {Object} Returns the `lodash` chainable object.
* @example
*
* var stooges = [
* { 'name': 'moe', 'age': 40 },
* { 'name': 'larry', 'age': 50 },
* { 'name': 'curly', 'age': 60 }
* ];
*
* var youngest = _.chain(stooges)
* .sortBy(function(stooge) { return stooge.age; })
* .map(function(stooge) { return stooge.name + ' is ' + stooge.age; })
* .first()
* .value();
* // => 'moe is 40'
*/
function chain(value) {
return lodash(value).chain();
}
/**
* Extracts the value from a wrapped chainable object.
*
* @name chain
* @memberOf _
* @category Chaining
* @returns {Mixed} Returns the wrapped object.
* @example
*
* _([1, 2, 3]).value();
* // => [1, 2, 3]
*/
function chainWrapper() {
this._chain = true;
return this;
}
/**
* Extracts the value from a wrapped chainable object.
*
* @memberOf _
* @category Chaining
* @returns {Mixed} Returns the wrapped object.
* @example
*
* _([1, 2, 3]).value();
* // => [1, 2, 3]
*/
function value() {
return this._wrapped;
}
/*--------------------------------------------------------------------------*/
/*
_.keys = nativeKeys ||
_.isArray = nativeIsArray || function(collection) {
if (!isArguments(arguments)) {
_.isArguments = function(collection) {
return !!(collection && hasOwnProperty.call(collection, 'callee'));
};
}
*/
/*--------------------------------------------------------------------------*/
/**
* The semantic version number.
*
* @static
* @memberOf _
* @type String
*/
lodash.VERSION = '1.3.3';
/**
* By default, Lodash uses ERB-style template delimiters, change the following
* template settings to use alternative delimiters.
*
* @static
* @memberOf _
* @type Object
*/
lodash.templateSettings = {
'evaluate': /<%([\s\S]+?)%>/g,
'interpolate': /<%=([\s\S]+?)%>/g,
'escape': /<%-([\s\S]+?)%>/g
};
// assign static properties
extend(lodash, {
'after': after,
'bind': bind,
'bindAll': bindAll,
'chain': chain,
'clone': clone,
'compact': compact,
'compose': compose,
'contains': contains,
'debounce': debounce,
'defaults': defaults,
'defer': defer,
'delay': delay,
'difference': difference,
'escape': escape,
'every': every,
'extend': extend,
'filter': filter,
'find': find,
'first': first,
'flatten': flatten,
'forEach': forEach,
'functions': functions,
'groupBy': groupBy,
'has': has,
'identity': identity,
'indexOf': indexOf,
'initial': initial,
'intersection': intersection,
'invoke': invoke,
'isArguments': isArguments,
'isArray': isArray,
'isBoolean': isBoolean,
'isDate': isDate,
'isElement': isElement,
'isEmpty': isEmpty,
'isEqual': isEqual,
'isFinite': isFinite,
'isFunction': isFunction,
'isNaN': isNaN,
'isNull': isNull,
'isNumber': isNumber,
'isObject': isObject,
'isRegExp': isRegExp,
'isString': isString,
'isUndefined': isUndefined,
'keys': keys,
'last': last,
'lastIndexOf': lastIndexOf,
'map': map,
'max': max,
'memoize': memoize,
'min': min,
'mixin': mixin,
'noConflict': noConflict,
'once': once,
'pick': pick,
'pluck': pluck,
'range': range,
'reduce': reduce,
'reduceRight': reduceRight,
'reject': reject,
'rest': rest,
'result': result,
'shuffle': shuffle,
'size': size,
'some': some,
'sortBy': sortBy,
'sortedIndex': sortedIndex,
'tap': tap,
'template': template,
'throttle': throttle,
'times': times,
'toArray': toArray,
'union': union,
'uniq': uniq,
'uniqueId': uniqueId,
'values': values,
'without': without,
'wrap': wrap,
'zip': zip
});
// assign aliases
extend(lodash, {
'all': every,
'any': some,
'collect': map,
'detect': find,
'each': forEach,
'foldl': reduce,
'foldr': reduceRight,
'head': first,
'include': contains,
'inject': reduce,
'intersect': intersection,
'methods': functions,
'select': filter,
'tail': rest,
'take': first,
'unique': uniq
});
/*--------------------------------------------------------------------------*/
// Expose `wrapper.prototype` as `_.prototype`
lodash.prototype = Wrapper.prototype;
// Add all of the Lo-Dash functions to the wrapper collection.
lodash.mixin(lodash);
// Add all mutator Array functions to the wrapper.
forEach(['pop', 'push', 'reverse', 'shift', 'sort', 'splice', 'unshift'], function(methodName) {
var func = ArrayProto[methodName];
Wrapper.prototype[methodName] = function() {
var wrapped = this._wrapped;
func.apply(wrapped, arguments);
// IE compatibility mode and IE < 9 have buggy Array `shift()` and `splice()`
// functions that fail to remove the last element, `object[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 length = wrapped.length;
if (length === 0) {
delete wrapped[0];
}
return this._chain ? lodash(wrapped).chain() : wrapped;
};
});
// Add all accessor Array functions to the wrapper.
forEach(['concat', 'join', 'slice'], function(methodName) {
var func = ArrayProto[methodName];
lodash.prototype[methodName] = function() {
var result = func.apply(this._wrapped, arguments);
return this._chain ? lodash(result).chain() : result;
};
});
extend(lodash.prototype, {
chain: chainWrapper,
value: value
});
/*--------------------------------------------------------------------------*/
// expose lodash
if (freeExports) {
// in Node.js or RingoJS v0.8.0+
if (typeof module == 'object' && module && module.exports == freeExports) {
(module.exports = lodash)._ = lodash;
}
// in Narwhal or RingoJS v0.7.0-
else {
freeExports._ = lodash;
}
}
// via an AMD loader
else if (typeof define == 'function' && typeof define.amd == 'object' && define.amd && define.amd.lodash) {
define('lodash', function() {
return lodash;
});
}
// in a browser or Rhino
else {
// use square bracket notation so Closure Compiler won't munge `_`
// http://code.google.com/closure/compiler/docs/api-tutorial3.html#export
window['_'] = lodash;
}
}(this));