/ajax/libs//0.1.1/underscore.js
JavaScript | 426 lines | 289 code | 52 blank | 85 comment | 68 complexity | f69d7a528a8ea0901ea6b5aee2860ae1 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/
- window.Underscore = {
-
- VERSION : '0.1.1',
-
- PREVIOUS_UNDERSCORE : window._,
-
- /*------------------------ 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;
- },
-
- // Inject builds up a single result from a list of values. Also known as
- // reduce, or foldl.
- inject : 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 _.inject(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 _.inject(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);
- var length = array.length;
- for (i=0; i<length; 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 window.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);
- };
- },
-
- /* ------------------------- 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() {
- window._ = Underscore.PREVIOUS_UNDERSCORE;
- 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;
- }
-
- };
- window._ = Underscore;