1 /*
  2     http://www.JSON.org/json2.js
  3     2009-08-17
  4 
  5     Public Domain.
  6 
  7     NO WARRANTY EXPRESSED OR IMPLIED. USE AT YOUR OWN RISK.
  8 
  9     See http://www.JSON.org/js.html
 10 
 11     This file creates a global JSON object containing two methods: stringify
 12     and parse.
 13 
 14         JSON.stringify(value, replacer, space)
 15             value       any JavaScript value, usually an object or array.
 16 
 17             replacer    an optional parameter that determines how object
 18                         values are stringified for objects. It can be a
 19                         function or an array of strings.
 20 
 21             space       an optional parameter that specifies the indentation
 22                         of nested structures. If it is omitted, the text will
 23                         be packed without extra whitespace. If it is a number,
 24                         it will specify the number of spaces to indent at each
 25                         level. If it is a string (such as '\t' or ' '),
 26                         it contains the characters used to indent at each level.
 27 
 28             This method produces a JSON text from a JavaScript value.
 29 
 30             When an object value is found, if the object contains a toJSON
 31             method, its toJSON method will be called and the result will be
 32             stringified. A toJSON method does not serialize: it returns the
 33             value represented by the name/value pair that should be serialized,
 34             or undefined if nothing should be serialized. The toJSON method
 35             will be passed the key associated with the value, and this will be
 36             bound to the value
 37 
 38             For example, this would serialize Dates as ISO strings.
 39 
 40                 Date.prototype.toJSON = function (key) {
 41                     function f(n) {
 42                         // Format integers to have at least two digits.
 43                         return n < 10 ? '0' + n : n;
 44                     }
 45 
 46                     return this.getUTCFullYear()   + '-' +
 47                          f(this.getUTCMonth() + 1) + '-' +
 48                          f(this.getUTCDate())      + 'T' +
 49                          f(this.getUTCHours())     + ':' +
 50                          f(this.getUTCMinutes())   + ':' +
 51                          f(this.getUTCSeconds())   + 'Z';
 52                 };
 53 
 54             You can provide an optional replacer method. It will be passed the
 55             key and value of each member, with this bound to the containing
 56             object. The value that is returned from your method will be
 57             serialized. If your method returns undefined, then the member will
 58             be excluded from the serialization.
 59 
 60             If the replacer parameter is an array of strings, then it will be
 61             used to select the members to be serialized. It filters the results
 62             such that only members with keys listed in the replacer array are
 63             stringified.
 64 
 65             Values that do not have JSON representations, such as undefined or
 66             functions, will not be serialized. Such values in objects will be
 67             dropped; in arrays they will be replaced with null. You can use
 68             a replacer function to replace those with JSON values.
 69             JSON.stringify(undefined) returns undefined.
 70 
 71             The optional space parameter produces a stringification of the
 72             value that is filled with line breaks and indentation to make it
 73             easier to read.
 74 
 75             If the space parameter is a non-empty string, then that string will
 76             be used for indentation. If the space parameter is a number, then
 77             the indentation will be that many spaces.
 78 
 79             Example:
 80 
 81             text = JSON.stringify(['e', {pluribus: 'unum'}]);
 82             // text is '["e",{"pluribus":"unum"}]'
 83 
 84 
 85             text = JSON.stringify(['e', {pluribus: 'unum'}], null, '\t');
 86             // text is '[\n\t"e",\n\t{\n\t\t"pluribus": "unum"\n\t}\n]'
 87 
 88             text = JSON.stringify([new Date()], function (key, value) {
 89                 return this[key] instanceof Date ?
 90                     'Date(' + this[key] + ')' : value;
 91             });
 92             // text is '["Date(---current time---)"]'
 93 
 94 
 95         JSON.parse(text, reviver)
 96             This method parses a JSON text to produce an object or array.
 97             It can throw a SyntaxError exception.
 98 
 99             The optional reviver parameter is a function that can filter and
100             transform the results. It receives each of the keys and values,
101             and its return value is used instead of the original value.
102             If it returns what it received, then the structure is not modified.
103             If it returns undefined then the member is deleted.
104 
105             Example:
106 
107             // Parse the text. Values that look like ISO date strings will
108             // be converted to Date objects.
109 
110             myData = JSON.parse(text, function (key, value) {
111                 var a;
112                 if (typeof value === 'string') {
113                     a =
114 /^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2}(?:\.\d*)?)Z$/.exec(value);
115                     if (a) {
116                         return new Date(Date.UTC(+a[1], +a[2] - 1, +a[3], +a[4],
117                             +a[5], +a[6]));
118                     }
119                 }
120                 return value;
121             });
122 
123             myData = JSON.parse('["Date(09/09/2001)"]', function (key, value) {
124                 var d;
125                 if (typeof value === 'string' &&
126                         value.slice(0, 5) === 'Date(' &&
127                         value.slice(-1) === ')') {
128                     d = new Date(value.slice(5, -1));
129                     if (d) {
130                         return d;
131                     }
132                 }
133                 return value;
134             });
135 
136 
137     This is a reference implementation. You are free to copy, modify, or
138     redistribute.
139 
140     This code should be minified before deployment.
141     See http://javascript.crockford.com/jsmin.html
142 
143     USE YOUR OWN COPY. IT IS EXTREMELY UNWISE TO LOAD CODE FROM SERVERS YOU DO
144     NOT CONTROL.
145 */
146 
147 /*jslint evil: true */
148 
149 /*members "", "\b", "\t", "\n", "\f", "\r", "\"", JSON, "\\", apply,
150     call, charCodeAt, getUTCDate, getUTCFullYear, getUTCHours,
151     getUTCMinutes, getUTCMonth, getUTCSeconds, hasOwnProperty, join,
152     lastIndex, length, parse, prototype, push, replace, slice, stringify,
153     test, toJSON, toString, valueOf
154 */
155 
156 "use strict";
157 
158 // Create a JSON object only if one does not already exist. We create the
159 // methods in a closure to avoid creating global variables.
160 
161 if (!this.JSON) {
162     this.JSON = {};
163 }
164 
165 (function () {
166 
167     function f(n) {
168         // Format integers to have at least two digits.
169         return n < 10 ? '0' + n : n;
170     }
171 
172     if (typeof Date.prototype.toJSON !== 'function') {
173 
174         Date.prototype.toJSON = function (key) {
175 
176             return isFinite(this.valueOf()) ?
177                    this.getUTCFullYear()   + '-' +
178                  f(this.getUTCMonth() + 1) + '-' +
179                  f(this.getUTCDate())      + 'T' +
180                  f(this.getUTCHours())     + ':' +
181                  f(this.getUTCMinutes())   + ':' +
182                  f(this.getUTCSeconds())   + 'Z' : null;
183         };
184 
185         String.prototype.toJSON =
186         Number.prototype.toJSON =
187         Boolean.prototype.toJSON = function (key) {
188             return this.valueOf();
189         };
190     }
191 
192     var cx = /[\u0000\u00ad\u0600-\u0604\u070f\u17b4\u17b5\u200c-\u200f\u2028-\u202f\u2060-\u206f\ufeff\ufff0-\uffff]/g,
193         escapable = /[\\\"\x00-\x1f\x7f-\x9f\u00ad\u0600-\u0604\u070f\u17b4\u17b5\u200c-\u200f\u2028-\u202f\u2060-\u206f\ufeff\ufff0-\uffff]/g,
194         gap,
195         indent,
196         meta = {    // table of character substitutions
197             '\b': '\\b',
198             '\t': '\\t',
199             '\n': '\\n',
200             '\f': '\\f',
201             '\r': '\\r',
202             '"' : '\\"',
203             '\\': '\\\\'
204         },
205         rep;
206 
207 
208     function quote(string) {
209 
210 // If the string contains no control characters, no quote characters, and no
211 // backslash characters, then we can safely slap some quotes around it.
212 // Otherwise we must also replace the offending characters with safe escape
213 // sequences.
214 
215         escapable.lastIndex = 0;
216         return escapable.test(string) ?
217             '"' + string.replace(escapable, function (a) {
218                 var c = meta[a];
219                 return typeof c === 'string' ? c :
220                     '\\u' + ('0000' + a.charCodeAt(0).toString(16)).slice(-4);
221             }) + '"' :
222             '"' + string + '"';
223     }
224 
225 
226     function str(key, holder) {
227 
228 // Produce a string from holder[key].
229 
230         var i,          // The loop counter.
231             k,          // The member key.
232             v,          // The member value.
233             length,
234             mind = gap,
235             partial,
236             value = holder[key];
237 
238 // If the value has a toJSON method, call it to obtain a replacement value.
239 
240         if (value && typeof value === 'object' &&
241                 typeof value.toJSON === 'function') {
242             value = value.toJSON(key);
243         }
244 
245 // If we were called with a replacer function, then call the replacer to
246 // obtain a replacement value.
247 
248         if (typeof rep === 'function') {
249             value = rep.call(holder, key, value);
250         }
251 
252 // What happens next depends on the value's type.
253 
254         switch (typeof value) {
255         case 'string':
256             return quote(value);
257 
258         case 'number':
259 
260 // JSON numbers must be finite. Encode non-finite numbers as null.
261 
262             return isFinite(value) ? String(value) : 'null';
263 
264         case 'boolean':
265         case 'null':
266 
267 // If the value is a boolean or null, convert it to a string. Note:
268 // typeof null does not produce 'null'. The case is included here in
269 // the remote chance that this gets fixed someday.
270 
271             return String(value);
272 
273 // If the type is 'object', we might be dealing with an object or an array or
274 // null.
275 
276         case 'object':
277 
278 // Due to a specification blunder in ECMAScript, typeof null is 'object',
279 // so watch out for that case.
280 
281             if (!value) {
282                 return 'null';
283             }
284 
285 // Make an array to hold the partial results of stringifying this object value.
286 
287             gap += indent;
288             partial = [];
289 
290 // Is the value an array?
291 
292             if (Object.prototype.toString.apply(value) === '[object Array]') {
293 
294 // The value is an array. Stringify every element. Use null as a placeholder
295 // for non-JSON values.
296 
297                 length = value.length;
298                 for (i = 0; i < length; i += 1) {
299                     partial[i] = str(i, value) || 'null';
300                 }
301 
302 // Join all of the elements together, separated with commas, and wrap them in
303 // brackets.
304 
305                 v = partial.length === 0 ? '[]' :
306                     gap ? '[\n' + gap +
307                             partial.join(',\n' + gap) + '\n' +
308                                 mind + ']' :
309                           '[' + partial.join(',') + ']';
310                 gap = mind;
311                 return v;
312             }
313 
314 // If the replacer is an array, use it to select the members to be stringified.
315 
316             if (rep && typeof rep === 'object') {
317                 length = rep.length;
318                 for (i = 0; i < length; i += 1) {
319                     k = rep[i];
320                     if (typeof k === 'string') {
321                         v = str(k, value);
322                         if (v) {
323                             partial.push(quote(k) + (gap ? ': ' : ':') + v);
324                         }
325                     }
326                 }
327             } else {
328 
329 // Otherwise, iterate through all of the keys in the object.
330 
331                 for (k in value) {
332                     if (Object.hasOwnProperty.call(value, k)) {
333                         v = str(k, value);
334                         if (v) {
335                             partial.push(quote(k) + (gap ? ': ' : ':') + v);
336                         }
337                     }
338                 }
339             }
340 
341 // Join all of the member texts together, separated with commas,
342 // and wrap them in braces.
343 
344             v = partial.length === 0 ? '{}' :
345                 gap ? '{\n' + gap + partial.join(',\n' + gap) + '\n' +
346                         mind + '}' : '{' + partial.join(',') + '}';
347             gap = mind;
348             return v;
349         }
350     }
351 
352 // If the JSON object does not yet have a stringify method, give it one.
353 
354     if (typeof JSON.stringify !== 'function') {
355         JSON.stringify = function (value, replacer, space) {
356 
357 // The stringify method takes a value and an optional replacer, and an optional
358 // space parameter, and returns a JSON text. The replacer can be a function
359 // that can replace values, or an array of strings that will select the keys.
360 // A default replacer method can be provided. Use of the space parameter can
361 // produce text that is more easily readable.
362 
363             var i;
364             gap = '';
365             indent = '';
366 
367 // If the space parameter is a number, make an indent string containing that
368 // many spaces.
369 
370             if (typeof space === 'number') {
371                 for (i = 0; i < space; i += 1) {
372                     indent += ' ';
373                 }
374 
375 // If the space parameter is a string, it will be used as the indent string.
376 
377             } else if (typeof space === 'string') {
378                 indent = space;
379             }
380 
381 // If there is a replacer, it must be a function or an array.
382 // Otherwise, throw an error.
383 
384             rep = replacer;
385             if (replacer && typeof replacer !== 'function' &&
386                     (typeof replacer !== 'object' ||
387                      typeof replacer.length !== 'number')) {
388                 throw new Error('JSON.stringify');
389             }
390 
391 // Make a fake root object containing our value under the key of ''.
392 // Return the result of stringifying the value.
393 
394             return str('', {'': value});
395         };
396     }
397 
398 
399 // If the JSON object does not yet have a parse method, give it one.
400 
401     if (typeof JSON.parse !== 'function') {
402         JSON.parse = function (text, reviver) {
403 
404 // The parse method takes a text and an optional reviver function, and returns
405 // a JavaScript value if the text is a valid JSON text.
406 
407             var j;
408 
409             function walk(holder, key) {
410 
411 // The walk method is used to recursively walk the resulting structure so
412 // that modifications can be made.
413 
414                 var k, v, value = holder[key];
415                 if (value && typeof value === 'object') {
416                     for (k in value) {
417                         if (Object.hasOwnProperty.call(value, k)) {
418                             v = walk(value, k);
419                             if (v !== undefined) {
420                                 value[k] = v;
421                             } else {
422                                 delete value[k];
423                             }
424                         }
425                     }
426                 }
427                 return reviver.call(holder, key, value);
428             }
429 
430 
431 // Parsing happens in four stages. In the first stage, we replace certain
432 // Unicode characters with escape sequences. JavaScript handles many characters
433 // incorrectly, either silently deleting them, or treating them as line endings.
434 
435             cx.lastIndex = 0;
436             if (cx.test(text)) {
437                 text = text.replace(cx, function (a) {
438                     return '\\u' +
439                         ('0000' + a.charCodeAt(0).toString(16)).slice(-4);
440                 });
441             }
442 
443 // In the second stage, we run the text against regular expressions that look
444 // for non-JSON patterns. We are especially concerned with '()' and 'new'
445 // because they can cause invocation, and '=' because it can cause mutation.
446 // But just to be safe, we want to reject all unexpected forms.
447 
448 // We split the second stage into 4 regexp operations in order to work around
449 // crippling inefficiencies in IE's and Safari's regexp engines. First we
450 // replace the JSON backslash pairs with '@' (a non-JSON character). Second, we
451 // replace all simple value tokens with ']' characters. Third, we delete all
452 // open brackets that follow a colon or comma or that begin the text. Finally,
453 // we look to see that the remaining characters are only whitespace or ']' or
454 // ',' or ':' or '{' or '}'. If that is so, then the text is safe for eval.
455 
456             if (/^[\],:{}\s]*$/.
457 test(text.replace(/\\(?:["\\\/bfnrt]|u[0-9a-fA-F]{4})/g, '@').
458 replace(/"[^"\\\n\r]*"|true|false|null|-?\d+(?:\.\d*)?(?:[eE][+\-]?\d+)?/g, ']').
459 replace(/(?:^|:|,)(?:\s*\[)+/g, ''))) {
460 
461 // In the third stage we use the eval function to compile the text into a
462 // JavaScript structure. The '{' operator is subject to a syntactic ambiguity
463 // in JavaScript: it can begin a block or an object literal. We wrap the text
464 // in parens to eliminate the ambiguity.
465 
466                 j = eval('(' + text + ')');
467 
468 // In the optional fourth stage, we recursively walk the new structure, passing
469 // each name/value pair to a reviver function for possible transformation.
470 
471                 return typeof reviver === 'function' ?
472                     walk({'': j}, '') : j;
473             }
474 
475 // If the text is not JSON parseable, then a SyntaxError is thrown.
476 
477             throw new SyntaxError('JSON.parse');
478         };
479     }
480 }());