PHP Classes

File: public/js/lib/json/cycle.js

Recommend this page to a friend!
  Classes of Sergey Beskorovayniy   Silex MVC Blog   public/js/lib/json/cycle.js   Download  
File: public/js/lib/json/cycle.js
Role: Auxiliary data
Content type: text/plain
Description: Auxiliary data
Class: Silex MVC Blog
MVC based blog using on the Silex micro-framework
Author: By
Last change:
Date: 8 years ago
Size: 6,213 bytes
 

Contents

Class file image Download
/* cycle.js 2013-02-19 Public Domain. NO WARRANTY EXPRESSED OR IMPLIED. USE AT YOUR OWN RISK. This code should be minified before deployment. See http://javascript.crockford.com/jsmin.html USE YOUR OWN COPY. IT IS EXTREMELY UNWISE TO LOAD CODE FROM SERVERS YOU DO NOT CONTROL. */ /*jslint evil: true, regexp: true */ /*members $ref, apply, call, decycle, hasOwnProperty, length, prototype, push, retrocycle, stringify, test, toString */ if (typeof JSON.decycle !== 'function') { JSON.decycle = function decycle(object) { 'use strict'; // Make a deep copy of an object or array, assuring that there is at most // one instance of each object or array in the resulting structure. The // duplicate references (which might be forming cycles) are replaced with // an object of the form // {$ref: PATH} // where the PATH is a JSONPath string that locates the first occurance. // So, // var a = []; // a[0] = a; // return JSON.stringify(JSON.decycle(a)); // produces the string '[{"$ref":"$"}]'. // JSONPath is used to locate the unique object. $ indicates the top level of // the object or array. [NUMBER] or [STRING] indicates a child member or // property. var objects = [], // Keep a reference to each unique object or array paths = []; // Keep the path to each unique object or array return (function derez(value, path) { // The derez recurses through the object, producing the deep copy. var i, // The loop counter name, // Property name nu; // The new object or array // typeof null === 'object', so go on if this value is really an object but not // one of the weird builtin objects. if (typeof value === 'object' && value !== null && !(value instanceof Boolean) && !(value instanceof Date) && !(value instanceof Number) && !(value instanceof RegExp) && !(value instanceof String)) { // If the value is an object or array, look to see if we have already // encountered it. If so, return a $ref/path object. This is a hard way, // linear search that will get slower as the number of unique objects grows. for (i = 0; i < objects.length; i += 1) { if (objects[i] === value) { return {$ref: paths[i]}; } } // Otherwise, accumulate the unique value and its path. objects.push(value); paths.push(path); // If it is an array, replicate the array. if (Object.prototype.toString.apply(value) === '[object Array]') { nu = []; for (i = 0; i < value.length; i += 1) { nu[i] = derez(value[i], path + '[' + i + ']'); } } else { // If it is an object, replicate the object. nu = {}; for (name in value) { if (Object.prototype.hasOwnProperty.call(value, name)) { nu[name] = derez(value[name], path + '[' + JSON.stringify(name) + ']'); } } } return nu; } return value; }(object, '$')); }; } if (typeof JSON.retrocycle !== 'function') { JSON.retrocycle = function retrocycle($) { 'use strict'; // Restore an object that was reduced by decycle. Members whose values are // objects of the form // {$ref: PATH} // are replaced with references to the value found by the PATH. This will // restore cycles. The object will be mutated. // The eval function is used to locate the values described by a PATH. The // root object is kept in a $ variable. A regular expression is used to // assure that the PATH is extremely well formed. The regexp contains nested // * quantifiers. That has been known to have extremely bad performance // problems on some browsers for very long strings. A PATH is expected to be // reasonably short. A PATH is allowed to belong to a very restricted subset of // Goessner's JSONPath. // So, // var s = '[{"$ref":"$"}]'; // return JSON.retrocycle(JSON.parse(s)); // produces an array containing a single element which is the array itself. var px = /^\$(?:\[(?:\d+|\"(?:[^\\\"\u0000-\u001f]|\\([\\\"\/bfnrt]|u[0-9a-zA-Z]{4}))*\")\])*$/; (function rez(value) { // The rez function walks recursively through the object looking for $ref // properties. When it finds one that has a value that is a path, then it // replaces the $ref object with a reference to the value that is found by // the path. var i, item, name, path; if (value && typeof value === 'object') { if (Object.prototype.toString.apply(value) === '[object Array]') { for (i = 0; i < value.length; i += 1) { item = value[i]; if (item && typeof item === 'object') { path = item.$ref; if (typeof path === 'string' && px.test(path)) { value[i] = eval(path); } else { rez(item); } } } } else { for (name in value) { if (typeof value[name] === 'object') { item = value[name]; if (item) { path = item.$ref; if (typeof path === 'string' && px.test(path)) { value[name] = eval(path); } else { rez(item); } } } } } } }($)); return $; }; }