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// http://underscorejs.org
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// (c) 2009-2012 Jeremy Ashkenas, DocumentCloud Inc.
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// Underscore may be freely distributed under the MIT license.
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// Establish the root object, `window` in the browser, or `global` on the server.
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// Save the previous value of the `_` variable.
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var previousUnderscore = root._;
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// Establish the object that gets returned to break out of a loop iteration.
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// Save bytes in the minified (but not gzipped) version:
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var ArrayProto = Array.prototype, ObjProto = Object.prototype, FuncProto = Function.prototype;
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// Create quick reference variables for speed access to core prototypes.
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var push = ArrayProto.push,
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slice = ArrayProto.slice,
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concat = ArrayProto.concat,
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unshift = ArrayProto.unshift,
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toString = ObjProto.toString,
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hasOwnProperty = ObjProto.hasOwnProperty;
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// All **ECMAScript 5** native function implementations that we hope to use
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nativeForEach = ArrayProto.forEach,
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nativeMap = ArrayProto.map,
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nativeReduce = ArrayProto.reduce,
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nativeReduceRight = ArrayProto.reduceRight,
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nativeFilter = ArrayProto.filter,
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nativeEvery = ArrayProto.every,
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nativeSome = ArrayProto.some,
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nativeIndexOf = ArrayProto.indexOf,
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nativeLastIndexOf = ArrayProto.lastIndexOf,
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nativeIsArray = Array.isArray,
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nativeKeys = Object.keys,
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nativeBind = FuncProto.bind;
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// Create a safe reference to the Underscore object for use below.
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var _ = function(obj) {
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if (obj instanceof _) return obj;
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if (!(this instanceof _)) return new _(obj);
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// Export the Underscore object for **Node.js**, with
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// backwards-compatibility for the old `require()` API. If we're in
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// the browser, add `_` as a global object via a string identifier,
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// for Closure Compiler "advanced" mode.
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if (typeof exports !== 'undefined') {
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if (typeof module !== 'undefined' && module.exports) {
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exports = module.exports = _;
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// Collection Functions
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// --------------------
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// The cornerstone, an `each` implementation, aka `forEach`.
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// Handles objects with the built-in `forEach`, arrays, and raw objects.
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// Delegates to **ECMAScript 5**'s native `forEach` if available.
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var each = _.each = _.forEach = function(obj, iterator, context) {
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if (obj == null) return;
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if (nativeForEach && obj.forEach === nativeForEach) {
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obj.forEach(iterator, context);
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} else if (obj.length === +obj.length) {
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for (var i = 0, l = obj.length; i < l; i++) {
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if (iterator.call(context, obj[i], i, obj) === breaker) return;
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for (var key in obj) {
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if (_.has(obj, key)) {
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if (iterator.call(context, obj[key], key, obj) === breaker) return;
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// Return the results of applying the iterator to each element.
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// Delegates to **ECMAScript 5**'s native `map` if available.
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_.map = _.collect = function(obj, iterator, context) {
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if (obj == null) return results;
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if (nativeMap && obj.map === nativeMap) return obj.map(iterator, context);
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each(obj, function(value, index, list) {
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results[results.length] = iterator.call(context, value, index, list);
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// **Reduce** builds up a single result from a list of values, aka `inject`,
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// or `foldl`. Delegates to **ECMAScript 5**'s native `reduce` if available.
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_.reduce = _.foldl = _.inject = function(obj, iterator, memo, context) {
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var initial = arguments.length > 2;
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if (obj == null) obj = [];
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if (nativeReduce && obj.reduce === nativeReduce) {
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if (context) iterator = _.bind(iterator, context);
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return initial ? obj.reduce(iterator, memo) : obj.reduce(iterator);
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each(obj, function(value, index, list) {
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memo = iterator.call(context, memo, value, index, list);
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if (!initial) throw new TypeError('Reduce of empty array with no initial value');
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// The right-associative version of reduce, also known as `foldr`.
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// Delegates to **ECMAScript 5**'s native `reduceRight` if available.
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_.reduceRight = _.foldr = function(obj, iterator, memo, context) {
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var initial = arguments.length > 2;
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if (obj == null) obj = [];
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if (nativeReduceRight && obj.reduceRight === nativeReduceRight) {
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if (context) iterator = _.bind(iterator, context);
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return arguments.length > 2 ? obj.reduceRight(iterator, memo) : obj.reduceRight(iterator);
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var length = obj.length;
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if (length !== +length) {
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var keys = _.keys(obj);
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length = keys.length;
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each(obj, function(value, index, list) {
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index = keys ? keys[--length] : --length;
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memo = iterator.call(context, memo, obj[index], index, list);
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if (!initial) throw new TypeError('Reduce of empty array with no initial value');
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// Return the first value which passes a truth test. Aliased as `detect`.
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_.find = _.detect = function(obj, iterator, context) {
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any(obj, function(value, index, list) {
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if (iterator.call(context, value, index, list)) {
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// Return all the elements that pass a truth test.
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// Delegates to **ECMAScript 5**'s native `filter` if available.
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// Aliased as `select`.
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_.filter = _.select = function(obj, iterator, context) {
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if (obj == null) return results;
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if (nativeFilter && obj.filter === nativeFilter) return obj.filter(iterator, context);
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each(obj, function(value, index, list) {
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if (iterator.call(context, value, index, list)) results[results.length] = value;
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// Return all the elements for which a truth test fails.
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_.reject = function(obj, iterator, context) {
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if (obj == null) return results;
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each(obj, function(value, index, list) {
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if (!iterator.call(context, value, index, list)) results[results.length] = value;
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// Determine whether all of the elements match a truth test.
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// Delegates to **ECMAScript 5**'s native `every` if available.
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_.every = _.all = function(obj, iterator, context) {
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iterator || (iterator = _.identity);
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if (obj == null) return result;
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if (nativeEvery && obj.every === nativeEvery) return obj.every(iterator, context);
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each(obj, function(value, index, list) {
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if (!(result = result && iterator.call(context, value, index, list))) return breaker;
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// Determine if at least one element in the object matches a truth test.
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// Delegates to **ECMAScript 5**'s native `some` if available.
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var any = _.some = _.any = function(obj, iterator, context) {
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iterator || (iterator = _.identity);
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if (obj == null) return result;
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if (nativeSome && obj.some === nativeSome) return obj.some(iterator, context);
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each(obj, function(value, index, list) {
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if (result || (result = iterator.call(context, value, index, list))) return breaker;
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// Determine if the array or object contains a given value (using `===`).
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// Aliased as `include`.
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_.contains = _.include = function(obj, target) {
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if (obj == null) return found;
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if (nativeIndexOf && obj.indexOf === nativeIndexOf) return obj.indexOf(target) != -1;
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found = any(obj, function(value) {
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return value === target;
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// Invoke a method (with arguments) on every item in a collection.
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_.invoke = function(obj, method) {
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var args = slice.call(arguments, 2);
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return _.map(obj, function(value) {
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return (_.isFunction(method) ? method : value[method]).apply(value, args);
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// Convenience version of a common use case of `map`: fetching a property.
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_.pluck = function(obj, key) {
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return _.map(obj, function(value){ return value[key]; });
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// Convenience version of a common use case of `filter`: selecting only objects
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// with specific `key:value` pairs.
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_.where = function(obj, attrs) {
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if (_.isEmpty(attrs)) return [];
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return _.filter(obj, function(value) {
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for (var key in attrs) {
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if (attrs[key] !== value[key]) return false;
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// Return the maximum element or (element-based computation).
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// Can't optimize arrays of integers longer than 65,535 elements.
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// See: https://bugs.webkit.org/show_bug.cgi?id=80797
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_.max = function(obj, iterator, context) {
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if (!iterator && _.isArray(obj) && obj[0] === +obj[0] && obj.length < 65535) {
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return Math.max.apply(Math, obj);
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if (!iterator && _.isEmpty(obj)) return -Infinity;
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var result = {computed : -Infinity};
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each(obj, function(value, index, list) {
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var computed = iterator ? iterator.call(context, value, index, list) : value;
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computed >= result.computed && (result = {value : value, computed : computed});
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// Return the minimum element (or element-based computation).
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_.min = function(obj, iterator, context) {
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if (!iterator && _.isArray(obj) && obj[0] === +obj[0] && obj.length < 65535) {
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return Math.min.apply(Math, obj);
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if (!iterator && _.isEmpty(obj)) return Infinity;
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var result = {computed : Infinity};
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each(obj, function(value, index, list) {
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var computed = iterator ? iterator.call(context, value, index, list) : value;
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computed < result.computed && (result = {value : value, computed : computed});
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_.shuffle = function(obj) {
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each(obj, function(value) {
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rand = _.random(index++);
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shuffled[index - 1] = shuffled[rand];
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shuffled[rand] = value;
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// An internal function to generate lookup iterators.
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var lookupIterator = function(value) {
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return _.isFunction(value) ? value : function(obj){ return obj[value]; };
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// Sort the object's values by a criterion produced by an iterator.
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_.sortBy = function(obj, value, context) {
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var iterator = lookupIterator(value);
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return _.pluck(_.map(obj, function(value, index, list) {
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criteria : iterator.call(context, value, index, list)
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}).sort(function(left, right) {
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var a = left.criteria;
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var b = right.criteria;
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if (a > b || a === void 0) return 1;
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if (a < b || b === void 0) return -1;
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return left.index < right.index ? -1 : 1;
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// An internal function used for aggregate "group by" operations.
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var group = function(obj, value, context, behavior) {
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var iterator = lookupIterator(value);
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each(obj, function(value, index) {
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var key = iterator.call(context, value, index, obj);
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behavior(result, key, value);
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// Groups the object's values by a criterion. Pass either a string attribute
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// to group by, or a function that returns the criterion.
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_.groupBy = function(obj, value, context) {
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return group(obj, value, context, function(result, key, value) {
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(_.has(result, key) ? result[key] : (result[key] = [])).push(value);
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// Counts instances of an object that group by a certain criterion. Pass
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// either a string attribute to count by, or a function that returns the
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_.countBy = function(obj, value, context) {
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return group(obj, value, context, function(result, key, value) {
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if (!_.has(result, key)) result[key] = 0;
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// Use a comparator function to figure out the smallest index at which
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// an object should be inserted so as to maintain order. Uses binary search.
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_.sortedIndex = function(array, obj, iterator, context) {
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iterator = iterator == null ? _.identity : lookupIterator(iterator);
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var value = iterator.call(context, obj);
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var low = 0, high = array.length;
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var mid = (low + high) >>> 1;
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iterator.call(context, array[mid]) < value ? low = mid + 1 : high = mid;
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// Safely convert anything iterable into a real, live array.
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_.toArray = function(obj) {
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if (obj.length === +obj.length) return slice.call(obj);
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return _.values(obj);
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// Return the number of elements in an object.
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_.size = function(obj) {
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return (obj.length === +obj.length) ? obj.length : _.keys(obj).length;
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// Get the first element of an array. Passing **n** will return the first N
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// values in the array. Aliased as `head` and `take`. The **guard** check
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// allows it to work with `_.map`.
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_.first = _.head = _.take = function(array, n, guard) {
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return (n != null) && !guard ? slice.call(array, 0, n) : array[0];
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// Returns everything but the last entry of the array. Especially useful on
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// the arguments object. Passing **n** will return all the values in
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// the array, excluding the last N. The **guard** check allows it to work with
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_.initial = function(array, n, guard) {
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return slice.call(array, 0, array.length - ((n == null) || guard ? 1 : n));
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// Get the last element of an array. Passing **n** will return the last N
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// values in the array. The **guard** check allows it to work with `_.map`.
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_.last = function(array, n, guard) {
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if ((n != null) && !guard) {
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return slice.call(array, Math.max(array.length - n, 0));
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return array[array.length - 1];
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// Returns everything but the first entry of the array. Aliased as `tail` and `drop`.
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// Especially useful on the arguments object. Passing an **n** will return
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// the rest N values in the array. The **guard**
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// check allows it to work with `_.map`.
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_.rest = _.tail = _.drop = function(array, n, guard) {
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return slice.call(array, (n == null) || guard ? 1 : n);
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// Trim out all falsy values from an array.
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_.compact = function(array) {
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return _.filter(array, function(value){ return !!value; });
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// Internal implementation of a recursive `flatten` function.
417
var flatten = function(input, shallow, output) {
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each(input, function(value) {
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if (_.isArray(value)) {
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shallow ? push.apply(output, value) : flatten(value, shallow, output);
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// Return a completely flattened version of an array.
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_.flatten = function(array, shallow) {
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return flatten(array, shallow, []);
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// Return a version of the array that does not contain the specified value(s).
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_.without = function(array) {
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return _.difference(array, slice.call(arguments, 1));
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// Produce a duplicate-free version of the array. If the array has already
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// been sorted, you have the option of using a faster algorithm.
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// Aliased as `unique`.
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_.uniq = _.unique = function(array, isSorted, iterator, context) {
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var initial = iterator ? _.map(array, iterator, context) : array;
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each(initial, function(value, index) {
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if (isSorted ? (!index || seen[seen.length - 1] !== value) : !_.contains(seen, value)) {
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results.push(array[index]);
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// Produce an array that contains the union: each distinct element from all of
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// the passed-in arrays.
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_.union = function() {
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return _.uniq(concat.apply(ArrayProto, arguments));
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// Produce an array that contains every item shared between all the
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_.intersection = function(array) {
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var rest = slice.call(arguments, 1);
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return _.filter(_.uniq(array), function(item) {
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return _.every(rest, function(other) {
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return _.indexOf(other, item) >= 0;
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// Take the difference between one array and a number of other arrays.
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// Only the elements present in just the first array will remain.
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_.difference = function(array) {
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var rest = concat.apply(ArrayProto, slice.call(arguments, 1));
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return _.filter(array, function(value){ return !_.contains(rest, value); });
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// Zip together multiple lists into a single array -- elements that share
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// an index go together.
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var args = slice.call(arguments);
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var length = _.max(_.pluck(args, 'length'));
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var results = new Array(length);
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for (var i = 0; i < length; i++) {
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results[i] = _.pluck(args, "" + i);
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// Converts lists into objects. Pass either a single array of `[key, value]`
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// pairs, or two parallel arrays of the same length -- one of keys, and one of
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// the corresponding values.
493
_.object = function(list, values) {
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for (var i = 0, l = list.length; i < l; i++) {
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result[list[i]] = values[i];
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result[list[i][0]] = list[i][1];
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// If the browser doesn't supply us with indexOf (I'm looking at you, **MSIE**),
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// we need this function. Return the position of the first occurrence of an
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// item in an array, or -1 if the item is not included in the array.
508
// Delegates to **ECMAScript 5**'s native `indexOf` if available.
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// If the array is large and already in sort order, pass `true`
510
// for **isSorted** to use binary search.
511
_.indexOf = function(array, item, isSorted) {
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if (array == null) return -1;
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var i = 0, l = array.length;
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if (typeof isSorted == 'number') {
516
i = (isSorted < 0 ? Math.max(0, l + isSorted) : isSorted);
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i = _.sortedIndex(array, item);
519
return array[i] === item ? i : -1;
522
if (nativeIndexOf && array.indexOf === nativeIndexOf) return array.indexOf(item, isSorted);
523
for (; i < l; i++) if (array[i] === item) return i;
527
// Delegates to **ECMAScript 5**'s native `lastIndexOf` if available.
528
_.lastIndexOf = function(array, item, from) {
529
if (array == null) return -1;
530
var hasIndex = from != null;
531
if (nativeLastIndexOf && array.lastIndexOf === nativeLastIndexOf) {
532
return hasIndex ? array.lastIndexOf(item, from) : array.lastIndexOf(item);
534
var i = (hasIndex ? from : array.length);
535
while (i--) if (array[i] === item) return i;
539
// Generate an integer Array containing an arithmetic progression. A port of
540
// the native Python `range()` function. See
541
// [the Python documentation](http://docs.python.org/library/functions.html#range).
542
_.range = function(start, stop, step) {
543
if (arguments.length <= 1) {
547
step = arguments[2] || 1;
549
var len = Math.max(Math.ceil((stop - start) / step), 0);
551
var range = new Array(len);
554
range[idx++] = start;
561
// Function (ahem) Functions
562
// ------------------
564
// Reusable constructor function for prototype setting.
565
var ctor = function(){};
567
// Create a function bound to a given object (assigning `this`, and arguments,
568
// optionally). Binding with arguments is also known as `curry`.
569
// Delegates to **ECMAScript 5**'s native `Function.bind` if available.
570
// We check for `func.bind` first, to fail fast when `func` is undefined.
571
_.bind = function bind(func, context) {
573
if (func.bind === nativeBind && nativeBind) return nativeBind.apply(func, slice.call(arguments, 1));
574
if (!_.isFunction(func)) throw new TypeError;
575
args = slice.call(arguments, 2);
576
return bound = function() {
577
if (!(this instanceof bound)) return func.apply(context, args.concat(slice.call(arguments)));
578
ctor.prototype = func.prototype;
580
var result = func.apply(self, args.concat(slice.call(arguments)));
581
if (Object(result) === result) return result;
586
// Bind all of an object's methods to that object. Useful for ensuring that
587
// all callbacks defined on an object belong to it.
588
_.bindAll = function(obj) {
589
var funcs = slice.call(arguments, 1);
590
if (funcs.length == 0) funcs = _.functions(obj);
591
each(funcs, function(f) { obj[f] = _.bind(obj[f], obj); });
595
// Memoize an expensive function by storing its results.
596
_.memoize = function(func, hasher) {
598
hasher || (hasher = _.identity);
600
var key = hasher.apply(this, arguments);
601
return _.has(memo, key) ? memo[key] : (memo[key] = func.apply(this, arguments));
605
// Delays a function for the given number of milliseconds, and then calls
606
// it with the arguments supplied.
607
_.delay = function(func, wait) {
608
var args = slice.call(arguments, 2);
609
return setTimeout(function(){ return func.apply(null, args); }, wait);
612
// Defers a function, scheduling it to run after the current call stack has
614
_.defer = function(func) {
615
return _.delay.apply(_, [func, 1].concat(slice.call(arguments, 1)));
618
// Returns a function, that, when invoked, will only be triggered at most once
619
// during a given window of time.
620
_.throttle = function(func, wait) {
621
var context, args, timeout, throttling, more, result;
622
var whenDone = _.debounce(function(){ more = throttling = false; }, wait);
624
context = this; args = arguments;
625
var later = function() {
628
result = func.apply(context, args);
632
if (!timeout) timeout = setTimeout(later, wait);
637
result = func.apply(context, args);
644
// Returns a function, that, as long as it continues to be invoked, will not
645
// be triggered. The function will be called after it stops being called for
646
// N milliseconds. If `immediate` is passed, trigger the function on the
647
// leading edge, instead of the trailing.
648
_.debounce = function(func, wait, immediate) {
651
var context = this, args = arguments;
652
var later = function() {
654
if (!immediate) result = func.apply(context, args);
656
var callNow = immediate && !timeout;
657
clearTimeout(timeout);
658
timeout = setTimeout(later, wait);
659
if (callNow) result = func.apply(context, args);
664
// Returns a function that will be executed at most one time, no matter how
665
// often you call it. Useful for lazy initialization.
666
_.once = function(func) {
667
var ran = false, memo;
669
if (ran) return memo;
671
memo = func.apply(this, arguments);
677
// Returns the first function passed as an argument to the second,
678
// allowing you to adjust arguments, run code before and after, and
679
// conditionally execute the original function.
680
_.wrap = function(func, wrapper) {
683
push.apply(args, arguments);
684
return wrapper.apply(this, args);
688
// Returns a function that is the composition of a list of functions, each
689
// consuming the return value of the function that follows.
690
_.compose = function() {
691
var funcs = arguments;
693
var args = arguments;
694
for (var i = funcs.length - 1; i >= 0; i--) {
695
args = [funcs[i].apply(this, args)];
701
// Returns a function that will only be executed after being called N times.
702
_.after = function(times, func) {
703
if (times <= 0) return func();
706
return func.apply(this, arguments);
714
// Retrieve the names of an object's properties.
715
// Delegates to **ECMAScript 5**'s native `Object.keys`
716
_.keys = nativeKeys || function(obj) {
717
if (obj !== Object(obj)) throw new TypeError('Invalid object');
719
for (var key in obj) if (_.has(obj, key)) keys[keys.length] = key;
723
// Retrieve the values of an object's properties.
724
_.values = function(obj) {
726
for (var key in obj) if (_.has(obj, key)) values.push(obj[key]);
730
// Convert an object into a list of `[key, value]` pairs.
731
_.pairs = function(obj) {
733
for (var key in obj) if (_.has(obj, key)) pairs.push([key, obj[key]]);
737
// Invert the keys and values of an object. The values must be serializable.
738
_.invert = function(obj) {
740
for (var key in obj) if (_.has(obj, key)) result[obj[key]] = key;
744
// Return a sorted list of the function names available on the object.
745
// Aliased as `methods`
746
_.functions = _.methods = function(obj) {
748
for (var key in obj) {
749
if (_.isFunction(obj[key])) names.push(key);
754
// Extend a given object with all the properties in passed-in object(s).
755
_.extend = function(obj) {
756
each(slice.call(arguments, 1), function(source) {
757
for (var prop in source) {
758
obj[prop] = source[prop];
764
// Return a copy of the object only containing the whitelisted properties.
765
_.pick = function(obj) {
767
var keys = concat.apply(ArrayProto, slice.call(arguments, 1));
768
each(keys, function(key) {
769
if (key in obj) copy[key] = obj[key];
774
// Return a copy of the object without the blacklisted properties.
775
_.omit = function(obj) {
777
var keys = concat.apply(ArrayProto, slice.call(arguments, 1));
778
for (var key in obj) {
779
if (!_.contains(keys, key)) copy[key] = obj[key];
784
// Fill in a given object with default properties.
785
_.defaults = function(obj) {
786
each(slice.call(arguments, 1), function(source) {
787
for (var prop in source) {
788
if (obj[prop] == null) obj[prop] = source[prop];
794
// Create a (shallow-cloned) duplicate of an object.
795
_.clone = function(obj) {
796
if (!_.isObject(obj)) return obj;
797
return _.isArray(obj) ? obj.slice() : _.extend({}, obj);
800
// Invokes interceptor with the obj, and then returns obj.
801
// The primary purpose of this method is to "tap into" a method chain, in
802
// order to perform operations on intermediate results within the chain.
803
_.tap = function(obj, interceptor) {
808
// Internal recursive comparison function for `isEqual`.
809
var eq = function(a, b, aStack, bStack) {
810
// Identical objects are equal. `0 === -0`, but they aren't identical.
811
// See the Harmony `egal` proposal: http://wiki.ecmascript.org/doku.php?id=harmony:egal.
812
if (a === b) return a !== 0 || 1 / a == 1 / b;
813
// A strict comparison is necessary because `null == undefined`.
814
if (a == null || b == null) return a === b;
815
// Unwrap any wrapped objects.
816
if (a instanceof _) a = a._wrapped;
817
if (b instanceof _) b = b._wrapped;
818
// Compare `[[Class]]` names.
819
var className = toString.call(a);
820
if (className != toString.call(b)) return false;
822
// Strings, numbers, dates, and booleans are compared by value.
823
case '[object String]':
824
// Primitives and their corresponding object wrappers are equivalent; thus, `"5"` is
825
// equivalent to `new String("5")`.
826
return a == String(b);
827
case '[object Number]':
828
// `NaN`s are equivalent, but non-reflexive. An `egal` comparison is performed for
829
// other numeric values.
830
return a != +a ? b != +b : (a == 0 ? 1 / a == 1 / b : a == +b);
831
case '[object Date]':
832
case '[object Boolean]':
833
// Coerce dates and booleans to numeric primitive values. Dates are compared by their
834
// millisecond representations. Note that invalid dates with millisecond representations
835
// of `NaN` are not equivalent.
837
// RegExps are compared by their source patterns and flags.
838
case '[object RegExp]':
839
return a.source == b.source &&
840
a.global == b.global &&
841
a.multiline == b.multiline &&
842
a.ignoreCase == b.ignoreCase;
844
if (typeof a != 'object' || typeof b != 'object') return false;
845
// Assume equality for cyclic structures. The algorithm for detecting cyclic
846
// structures is adapted from ES 5.1 section 15.12.3, abstract operation `JO`.
847
var length = aStack.length;
849
// Linear search. Performance is inversely proportional to the number of
850
// unique nested structures.
851
if (aStack[length] == a) return bStack[length] == b;
853
// Add the first object to the stack of traversed objects.
856
var size = 0, result = true;
857
// Recursively compare objects and arrays.
858
if (className == '[object Array]') {
859
// Compare array lengths to determine if a deep comparison is necessary.
861
result = size == b.length;
863
// Deep compare the contents, ignoring non-numeric properties.
865
if (!(result = eq(a[size], b[size], aStack, bStack))) break;
869
// Objects with different constructors are not equivalent, but `Object`s
870
// from different frames are.
871
var aCtor = a.constructor, bCtor = b.constructor;
872
if (aCtor !== bCtor && !(_.isFunction(aCtor) && (aCtor instanceof aCtor) &&
873
_.isFunction(bCtor) && (bCtor instanceof bCtor))) {
876
// Deep compare objects.
879
// Count the expected number of properties.
881
// Deep compare each member.
882
if (!(result = _.has(b, key) && eq(a[key], b[key], aStack, bStack))) break;
885
// Ensure that both objects contain the same number of properties.
888
if (_.has(b, key) && !(size--)) break;
893
// Remove the first object from the stack of traversed objects.
899
// Perform a deep comparison to check if two objects are equal.
900
_.isEqual = function(a, b) {
901
return eq(a, b, [], []);
904
// Is a given array, string, or object empty?
905
// An "empty" object has no enumerable own-properties.
906
_.isEmpty = function(obj) {
907
if (obj == null) return true;
908
if (_.isArray(obj) || _.isString(obj)) return obj.length === 0;
909
for (var key in obj) if (_.has(obj, key)) return false;
913
// Is a given value a DOM element?
914
_.isElement = function(obj) {
915
return !!(obj && obj.nodeType === 1);
918
// Is a given value an array?
919
// Delegates to ECMA5's native Array.isArray
920
_.isArray = nativeIsArray || function(obj) {
921
return toString.call(obj) == '[object Array]';
924
// Is a given variable an object?
925
_.isObject = function(obj) {
926
return obj === Object(obj);
929
// Add some isType methods: isArguments, isFunction, isString, isNumber, isDate, isRegExp.
930
each(['Arguments', 'Function', 'String', 'Number', 'Date', 'RegExp'], function(name) {
931
_['is' + name] = function(obj) {
932
return toString.call(obj) == '[object ' + name + ']';
936
// Define a fallback version of the method in browsers (ahem, IE), where
937
// there isn't any inspectable "Arguments" type.
938
if (!_.isArguments(arguments)) {
939
_.isArguments = function(obj) {
940
return !!(obj && _.has(obj, 'callee'));
944
// Optimize `isFunction` if appropriate.
945
if (typeof (/./) !== 'function') {
946
_.isFunction = function(obj) {
947
return typeof obj === 'function';
951
// Is a given object a finite number?
952
_.isFinite = function(obj) {
953
return _.isNumber(obj) && isFinite(obj);
956
// Is the given value `NaN`? (NaN is the only number which does not equal itself).
957
_.isNaN = function(obj) {
958
return _.isNumber(obj) && obj != +obj;
961
// Is a given value a boolean?
962
_.isBoolean = function(obj) {
963
return obj === true || obj === false || toString.call(obj) == '[object Boolean]';
966
// Is a given value equal to null?
967
_.isNull = function(obj) {
971
// Is a given variable undefined?
972
_.isUndefined = function(obj) {
973
return obj === void 0;
976
// Shortcut function for checking if an object has a given property directly
977
// on itself (in other words, not on a prototype).
978
_.has = function(obj, key) {
979
return hasOwnProperty.call(obj, key);
985
// Run Underscore.js in *noConflict* mode, returning the `_` variable to its
986
// previous owner. Returns a reference to the Underscore object.
987
_.noConflict = function() {
988
root._ = previousUnderscore;
992
// Keep the identity function around for default iterators.
993
_.identity = function(value) {
997
// Run a function **n** times.
998
_.times = function(n, iterator, context) {
999
for (var i = 0; i < n; i++) iterator.call(context, i);
1002
// Return a random integer between min and max (inclusive).
1003
_.random = function(min, max) {
1008
return min + (0 | Math.random() * (max - min + 1));
1011
// List of HTML entities for escaping.
1022
entityMap.unescape = _.invert(entityMap.escape);
1024
// Regexes containing the keys and values listed immediately above.
1025
var entityRegexes = {
1026
escape: new RegExp('[' + _.keys(entityMap.escape).join('') + ']', 'g'),
1027
unescape: new RegExp('(' + _.keys(entityMap.unescape).join('|') + ')', 'g')
1030
// Functions for escaping and unescaping strings to/from HTML interpolation.
1031
_.each(['escape', 'unescape'], function(method) {
1032
_[method] = function(string) {
1033
if (string == null) return '';
1034
return ('' + string).replace(entityRegexes[method], function(match) {
1035
return entityMap[method][match];
1040
// If the value of the named property is a function then invoke it;
1041
// otherwise, return it.
1042
_.result = function(object, property) {
1043
if (object == null) return null;
1044
var value = object[property];
1045
return _.isFunction(value) ? value.call(object) : value;
1048
// Add your own custom functions to the Underscore object.
1049
_.mixin = function(obj) {
1050
each(_.functions(obj), function(name){
1051
var func = _[name] = obj[name];
1052
_.prototype[name] = function() {
1053
var args = [this._wrapped];
1054
push.apply(args, arguments);
1055
return result.call(this, func.apply(_, args));
1060
// Generate a unique integer id (unique within the entire client session).
1061
// Useful for temporary DOM ids.
1063
_.uniqueId = function(prefix) {
1064
var id = idCounter++;
1065
return prefix ? prefix + id : id;
1068
// By default, Underscore uses ERB-style template delimiters, change the
1069
// following template settings to use alternative delimiters.
1070
_.templateSettings = {
1071
evaluate : /<%([\s\S]+?)%>/g,
1072
interpolate : /<%=([\s\S]+?)%>/g,
1073
escape : /<%-([\s\S]+?)%>/g
1076
// When customizing `templateSettings`, if you don't want to define an
1077
// interpolation, evaluation or escaping regex, we need one that is
1078
// guaranteed not to match.
1079
var noMatch = /(.)^/;
1081
// Certain characters need to be escaped so that they can be put into a
1093
var escaper = /\\|'|\r|\n|\t|\u2028|\u2029/g;
1095
// JavaScript micro-templating, similar to John Resig's implementation.
1096
// Underscore templating handles arbitrary delimiters, preserves whitespace,
1097
// and correctly escapes quotes within interpolated code.
1098
_.template = function(text, data, settings) {
1099
settings = _.defaults({}, settings, _.templateSettings);
1101
// Combine delimiters into one regular expression via alternation.
1102
var matcher = new RegExp([
1103
(settings.escape || noMatch).source,
1104
(settings.interpolate || noMatch).source,
1105
(settings.evaluate || noMatch).source
1106
].join('|') + '|$', 'g');
1108
// Compile the template source, escaping string literals appropriately.
1110
var source = "__p+='";
1111
text.replace(matcher, function(match, escape, interpolate, evaluate, offset) {
1112
source += text.slice(index, offset)
1113
.replace(escaper, function(match) { return '\\' + escapes[match]; });
1115
escape ? "'+\n((__t=(" + escape + "))==null?'':_.escape(__t))+\n'" :
1116
interpolate ? "'+\n((__t=(" + interpolate + "))==null?'':__t)+\n'" :
1117
evaluate ? "';\n" + evaluate + "\n__p+='" : '';
1118
index = offset + match.length;
1122
// If a variable is not specified, place data values in local scope.
1123
if (!settings.variable) source = 'with(obj||{}){\n' + source + '}\n';
1125
source = "var __t,__p='',__j=Array.prototype.join," +
1126
"print=function(){__p+=__j.call(arguments,'');};\n" +
1127
source + "return __p;\n";
1130
var render = new Function(settings.variable || 'obj', '_', source);
1136
if (data) return render(data, _);
1137
var template = function(data) {
1138
return render.call(this, data, _);
1141
// Provide the compiled function source as a convenience for precompilation.
1142
template.source = 'function(' + (settings.variable || 'obj') + '){\n' + source + '}';
1147
// Add a "chain" function, which will delegate to the wrapper.
1148
_.chain = function(obj) {
1149
return _(obj).chain();
1154
// If Underscore is called as a function, it returns a wrapped object that
1155
// can be used OO-style. This wrapper holds altered versions of all the
1156
// underscore functions. Wrapped objects may be chained.
1158
// Helper function to continue chaining intermediate results.
1159
var result = function(obj) {
1160
return this._chain ? _(obj).chain() : obj;
1163
// Add all of the Underscore functions to the wrapper object.
1166
// Add all mutator Array functions to the wrapper.
1167
each(['pop', 'push', 'reverse', 'shift', 'sort', 'splice', 'unshift'], function(name) {
1168
var method = ArrayProto[name];
1169
_.prototype[name] = function() {
1170
var obj = this._wrapped;
1171
method.apply(obj, arguments);
1172
if ((name == 'shift' || name == 'splice') && obj.length === 0) delete obj[0];
1173
return result.call(this, obj);
1177
// Add all accessor Array functions to the wrapper.
1178
each(['concat', 'join', 'slice'], function(name) {
1179
var method = ArrayProto[name];
1180
_.prototype[name] = function() {
1181
return result.call(this, method.apply(this._wrapped, arguments));
1185
_.extend(_.prototype, {
1187
// Start chaining a wrapped Underscore object.
1193
// Extracts the result from a wrapped and chained object.
1195
return this._wrapped;
added
removed
tests/embind/underscore-1.4.2.js
