/ajax/libs//0.2.0/underscore.js
JavaScript | 460 lines | 309 code | 60 blank | 91 comment | 74 complexity | 57d6bd674e13a0657f706c1c26f506f1 MD5 | raw file
- // Underscore.js
- // (c) 2009 Jeremy Ashkenas, DocumentCloud Inc.
- // Underscore is freely distributable under the terms of the MIT license.
- // Portions of Underscore are inspired by or borrowed from Prototype.js,
- // Oliver Steele's Functional, And John Resig's Micro-Templating.
- // For all details and documentation:
- // http://documentcloud.github.com/underscore/
- (function() {
-
- var root = (typeof window != 'undefined') ? window : exports;
-
- var previousUnderscore = root._;
-
- var _ = root._ = {};
-
- _.VERSION = '0.2.0';
-
- /*------------------------ Collection Functions: ---------------------------*/
-
- // The cornerstone, an each implementation.
- // Handles objects implementing forEach, each, arrays, and raw objects.
- _.each = function(obj, iterator, context) {
- var index = 0;
- try {
- if (obj.forEach) {
- obj.forEach(iterator, context);
- } else if (obj.length) {
- for (var i=0; i<obj.length; i++) iterator.call(context, obj[i], i);
- } else if (obj.each) {
- obj.each(function(value) { iterator.call(context, value, index++); });
- } else {
- var i = 0;
- for (var key in obj) {
- var value = obj[key], pair = [key, value];
- pair.key = key;
- pair.value = value;
- iterator.call(context, pair, i++);
- }
- }
- } catch(e) {
- if (e != '__break__') throw e;
- }
- return obj;
- };
-
- // Return the results of applying the iterator to each element. Use Javascript
- // 1.6's version of map, if possible.
- _.map = function(obj, iterator, context) {
- if (obj && obj.map) return obj.map(iterator, context);
- var results = [];
- _.each(obj, function(value, index) {
- results.push(iterator.call(context, value, index));
- });
- return results;
- };
-
- // Reduce builds up a single result from a list of values. Also known as
- // inject, or foldl.
- _.reduce = function(obj, memo, iterator, context) {
- _.each(obj, function(value, index) {
- memo = iterator.call(context, memo, value, index);
- });
- return memo;
- };
-
- // Return the first value which passes a truth test.
- _.detect = function(obj, iterator, context) {
- var result;
- _.each(obj, function(value, index) {
- if (iterator.call(context, value, index)) {
- result = value;
- throw '__break__';
- }
- });
- return result;
- };
-
- // Return all the elements that pass a truth test. Use Javascript 1.6's
- // filter(), if it exists.
- _.select = function(obj, iterator, context) {
- if (obj.filter) return obj.filter(iterator, context);
- var results = [];
- _.each(obj, function(value, index) {
- if (iterator.call(context, value, index)) results.push(value);
- });
- return results;
- };
-
- // Return all the elements for which a truth test fails.
- _.reject = function(obj, iterator, context) {
- var results = [];
- _.each(obj, function(value, index) {
- if (!iterator.call(context, value, index)) results.push(value);
- });
- return results;
- };
-
- // Determine whether all of the elements match a truth test. Delegate to
- // Javascript 1.6's every(), if it is present.
- _.all = function(obj, iterator, context) {
- iterator = iterator || function(v){ return v; };
- if (obj.every) return obj.every(iterator, context);
- var result = true;
- _.each(obj, function(value, index) {
- result = result && !!iterator.call(context, value, index);
- if (!result) throw '__break__';
- });
- return result;
- };
-
- // Determine if at least one element in the object matches a truth test. Use
- // Javascript 1.6's some(), if it exists.
- _.any = function(obj, iterator, context) {
- iterator = iterator || function(v) { return v; };
- if (obj.some) return obj.some(iterator, context);
- var result = false;
- _.each(obj, function(value, index) {
- if (result = !!iterator.call(context, value, index)) throw '__break__';
- });
- return result;
- };
-
- // Determine if a given value is included in the array or object,
- // based on '==='.
- _.include = function(obj, target) {
- if (_.isArray(obj)) return _.indexOf(obj, target) != -1;
- var found = false;
- _.each(obj, function(pair) {
- if (pair.value === target) {
- found = true;
- throw '__break__';
- }
- });
- return found;
- };
-
- // Invoke a method with arguments on every item in a collection.
- _.invoke = function(obj, method) {
- var args = _.toArray(arguments).slice(2);
- return _.map(obj, function(value) {
- return (method ? value[method] : value).apply(value, args);
- });
- };
-
- // Optimized version of a common use case of map: fetching a property.
- _.pluck = function(obj, key) {
- var results = [];
- _.each(obj, function(value){ results.push(value[key]); });
- return results;
- };
-
- // Return the maximum item or (item-based computation).
- _.max = function(obj, iterator, context) {
- if (!iterator && _.isArray(obj)) return Math.max.apply(Math, obj);
- var result;
- _.each(obj, function(value, index) {
- var computed = iterator ? iterator.call(context, value, index) : value;
- if (result == null || computed >= result.computed) result = {value : value, computed : computed};
- });
- return result.value;
- };
-
- // Return the minimum element (or element-based computation).
- _.min = function(obj, iterator, context) {
- if (!iterator && _.isArray(obj)) return Math.min.apply(Math, obj);
- var result;
- _.each(obj, function(value, index) {
- var computed = iterator ? iterator.call(context, value, index) : value;
- if (result == null || computed < result.computed) result = {value : value, computed : computed};
- });
- return result.value;
- };
-
- // Sort the object's values by a criteria produced by an iterator.
- _.sortBy = function(obj, iterator, context) {
- return _.pluck(_.map(obj, function(value, index) {
- return {
- value : value,
- criteria : iterator.call(context, value, index)
- };
- }).sort(function(left, right) {
- var a = left.criteria, b = right.criteria;
- return a < b ? -1 : a > b ? 1 : 0;
- }), 'value');
- };
-
- // Use a comparator function to figure out at what index an object should
- // be inserted so as to maintain order. Uses binary search.
- _.sortedIndex = function(array, obj, iterator) {
- iterator = iterator || function(val) { return val; };
- var low = 0, high = array.length;
- while (low < high) {
- var mid = (low + high) >> 1;
- iterator(array[mid]) < iterator(obj) ? low = mid + 1 : high = mid;
- }
- return low;
- };
-
- // Convert anything iterable into a real, live array.
- _.toArray = function(iterable) {
- if (!iterable) return [];
- if (_.isArray(iterable)) return iterable;
- return _.map(iterable, function(val){ return val; });
- };
-
- // Return the number of elements in an object.
- _.size = function(obj) {
- return _.toArray(obj).length;
- };
-
- /*-------------------------- Array Functions: ------------------------------*/
-
- // Get the first element of an array.
- _.first = function(array) {
- return array[0];
- };
-
- // Get the last element of an array.
- _.last = function(array) {
- return array[array.length - 1];
- };
-
- // Trim out all falsy values from an array.
- _.compact = function(array) {
- return _.select(array, function(value){ return !!value; });
- };
-
- // Return a completely flattened version of an array.
- _.flatten = function(array) {
- return _.reduce(array, [], function(memo, value) {
- if (_.isArray(value)) return memo.concat(_.flatten(value));
- memo.push(value);
- return memo;
- });
- };
-
- // Return a version of the array that does not contain the specified value(s).
- _.without = function(array) {
- var values = array.slice.call(arguments, 0);
- return _.select(array, function(value){ return !_.include(values, value); });
- };
-
- // Produce a duplicate-free version of the array. If the array has already
- // been sorted, you have the option of using a faster algorithm.
- _.uniq = function(array, isSorted) {
- return _.reduce(array, [], function(memo, el, i) {
- if (0 == i || (isSorted ? _.last(memo) != el : !_.include(memo, el))) memo.push(el);
- return memo;
- });
- };
-
- // Produce an array that contains every item shared between all the
- // passed-in arrays.
- _.intersect = function(array) {
- var rest = _.toArray(arguments).slice(1);
- return _.select(_.uniq(array), function(item) {
- return _.all(rest, function(other) {
- return _.indexOf(other, item) >= 0;
- });
- });
- };
-
- // Zip together multiple lists into a single array -- elements that share
- // an index go together.
- _.zip = function() {
- var args = _.toArray(arguments);
- var length = _.max(_.pluck(args, 'length'));
- var results = new Array(length);
- for (var i=0; i<length; i++) results[i] = _.pluck(args, String(i));
- return results;
- };
-
- // If the browser doesn't supply us with indexOf (I'm looking at you, MSIE),
- // we need this function. Return the position of the first occurence of an
- // item in an array, or -1 if the item is not included in the array.
- _.indexOf = function(array, item) {
- if (array.indexOf) return array.indexOf(item);
- for (i=0; i<array.length; i++) if (array[i] === item) return i;
- return -1;
- };
-
- // Provide Javascript 1.6's lastIndexOf, delegating to the native function,
- // if possible.
- _.lastIndexOf = function(array, item) {
- if (array.lastIndexOf) return array.lastIndexOf(item);
- for (i=array.length - 1; i>=0; i--) if (array[i] === item) return i;
- return -1;
- };
-
- /* ----------------------- Function Functions: -----------------------------*/
-
- // Create a function bound to a given object (assigning 'this', and arguments,
- // optionally). Binding with arguments is also known as 'curry'.
- _.bind = function(func, context) {
- if (!context) return func;
- var args = _.toArray(arguments).slice(2);
- return function() {
- var a = args.concat(_.toArray(arguments));
- return func.apply(context, a);
- };
- };
-
- // Bind all of an object's methods to that object. Useful for ensuring that
- // all callbacks defined on an object belong to it.
- _.bindAll = function() {
- var args = _.toArray(arguments);
- var context = args.pop();
- _.each(args, function(methodName) {
- context[methodName] = _.bind(context[methodName], context);
- });
- };
-
- // Delays a function for the given number of milliseconds, and then calls
- // it with the arguments supplied.
- _.delay = function(func, wait) {
- var args = _.toArray(arguments).slice(2);
- return setTimeout(function(){ return func.apply(func, args); }, wait);
- };
-
- // Defers a function, scheduling it to run after the current call stack has
- // cleared.
- _.defer = function(func) {
- return _.delay.apply(_, [func, 1].concat(_.toArray(arguments).slice(1)));
- };
-
- // Returns the first function passed as an argument to the second,
- // allowing you to adjust arguments, run code before and after, and
- // conditionally execute the original function.
- _.wrap = function(func, wrapper) {
- return function() {
- var args = [func].concat(_.toArray(arguments));
- return wrapper.apply(wrapper, args);
- };
- };
-
- // Returns a function that is the composition of a list of functions, each
- // consuming the return value of the function that follows.
- _.compose = function() {
- var funcs = _.toArray(arguments);
- return function() {
- for (var i=funcs.length-1; i >= 0; i--) {
- arguments = [funcs[i].apply(this, arguments)];
- }
- return arguments[0];
- };
- };
-
- /* ------------------------- Object Functions: ---------------------------- */
-
- // Retrieve the names of an object's properties.
- _.keys = function(obj) {
- return _.pluck(obj, 'key');
- };
-
- // Retrieve the values of an object's properties.
- _.values = function(obj) {
- return _.pluck(obj, 'value');
- };
-
- // Extend a given object with all of the properties in a source object.
- _.extend = function(destination, source) {
- for (var property in source) destination[property] = source[property];
- return destination;
- };
-
- // Create a (shallow-cloned) duplicate of an object.
- _.clone = function(obj) {
- return _.extend({}, obj);
- };
-
- // Perform a deep comparison to check if two objects are equal.
- _.isEqual = function(a, b) {
- // Check object identity.
- if (a === b) return true;
- // Different types?
- var atype = typeof(a), btype = typeof(b);
- if (atype != btype) return false;
- // Basic equality test (watch out for coercions).
- if (a == b) return true;
- // One of them implements an isEqual()?
- if (a.isEqual) return a.isEqual(b);
- // If a is not an object by this point, we can't handle it.
- if (atype !== 'object') return false;
- // Nothing else worked, deep compare the contents.
- var aKeys = _.keys(a), bKeys = _.keys(b);
- // Different object sizes?
- if (aKeys.length != bKeys.length) return false;
- // Recursive comparison of contents.
- for (var key in a) if (!_.isEqual(a[key], b[key])) return false;
- return true;
- };
-
- // Is a given value a DOM element?
- _.isElement = function(obj) {
- return !!(obj && obj.nodeType == 1);
- };
-
- // Is a given value a real Array?
- _.isArray = function(obj) {
- return Object.prototype.toString.call(obj) == '[object Array]';
- };
-
- // Is a given value a Function?
- _.isFunction = function(obj) {
- return typeof obj == 'function';
- };
-
- // Is a given variable undefined?
- _.isUndefined = function(obj) {
- return typeof obj == 'undefined';
- };
-
- /* -------------------------- Utility Functions: -------------------------- */
-
- // Run Underscore.js in noConflict mode, returning the '_' variable to its
- // previous owner. Returns a reference to the Underscore object.
- _.noConflict = function() {
- root._ = previousUnderscore;
- return this;
- };
-
- // Generate a unique integer id (unique within the entire client session).
- // Useful for temporary DOM ids.
- _.uniqueId = function(prefix) {
- var id = this._idCounter = (this._idCounter || 0) + 1;
- return prefix ? prefix + id : id;
- };
-
- // Javascript templating a-la ERB, pilfered from John Resig's
- // "Secrets of the Javascript Ninja", page 83.
- _.template = function(str, data) {
- var fn = new Function('obj',
- 'var p=[],print=function(){p.push.apply(p,arguments);};' +
- 'with(obj){p.push(\'' +
- str
- .replace(/[\r\t\n]/g, " ")
- .split("<%").join("\t")
- .replace(/((^|%>)[^\t]*)'/g, "$1\r")
- .replace(/\t=(.*?)%>/g, "',$1,'")
- .split("\t").join("');")
- .split("%>").join("p.push('")
- .split("\r").join("\\'")
- + "');}return p.join('');");
- return data ? fn(data) : fn;
- };
-
- /*------------------------------- Aliases ----------------------------------*/
- _.forEach = _.each;
- _.inject = _.reduce;
- _.filter = _.select;
- _.every = _.all;
- _.some = _.any;
-
- /*------------------------- Export for ServerJS ----------------------------*/
-
- if (!_.isUndefined(exports)) exports = _;
- })();