1 /*
  2     http://www.JSON.org/json2.js
  3     2008-11-19
  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 object holding the key.
 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 /*global JSON */
150 
151 /*members "", "\b", "\t", "\n", "\f", "\r", "\"", JSON, "\\", apply,
152     call, charCodeAt, getUTCDate, getUTCFullYear, getUTCHours,
153     getUTCMinutes, getUTCMonth, getUTCSeconds, hasOwnProperty, join,
154     lastIndex, length, parse, prototype, push, replace, slice, stringify,
155     test, toJSON, toString, valueOf
156 */
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     JSON = {};
163 }
164 (function () {
165 
166     function f(n) {
167         // Format integers to have at least two digits.
168         return n < 10 ? '0' + n : n;
169     }
170 
171     if (typeof Date.prototype.toJSON !== 'function') {
172 
173         Date.prototype.toJSON = function (key) {
174 
175             return this.getUTCFullYear()   + '-' +
176                  f(this.getUTCMonth() + 1) + '-' +
177                  f(this.getUTCDate())      + 'T' +
178                  f(this.getUTCHours())     + ':' +
179                  f(this.getUTCMinutes())   + ':' +
180                  f(this.getUTCSeconds())   + 'Z';
181         };
182 
183         String.prototype.toJSON =
184         Number.prototype.toJSON =
185         Boolean.prototype.toJSON = function (key) {
186             return this.valueOf();
187         };
188     }
189 
190     var cx = /[\u0000\u00ad\u0600-\u0604\u070f\u17b4\u17b5\u200c-\u200f\u2028-\u202f\u2060-\u206f\ufeff\ufff0-\uffff]/g,
191         escapable = /[\\\"\x00-\x1f\x7f-\x9f\u00ad\u0600-\u0604\u070f\u17b4\u17b5\u200c-\u200f\u2028-\u202f\u2060-\u206f\ufeff\ufff0-\uffff]/g,
192         gap,
193         indent,
194         meta = {    // table of character substitutions
195             '\b': '\\b',
196             '\t': '\\t',
197             '\n': '\\n',
198             '\f': '\\f',
199             '\r': '\\r',
200             '"' : '\\"',
201             '\\': '\\\\'
202         },
203         rep;
204 
205 
206     function quote(string) {
207 
208 // If the string contains no control characters, no quote characters, and no
209 // backslash characters, then we can safely slap some quotes around it.
210 // Otherwise we must also replace the offending characters with safe escape
211 // sequences.
212 
213         escapable.lastIndex = 0;
214         return escapable.test(string) ?
215             '"' + string.replace(escapable, function (a) {
216                 var c = meta[a];
217                 return typeof c === 'string' ? c :
218                     '\\u' + ('0000' + a.charCodeAt(0).toString(16)).slice(-4);
219             }) + '"' :
220             '"' + string + '"';
221     }
222 
223 
224     function str(key, holder) {
225 
226 // Produce a string from holder[key].
227 
228         var i,          // The loop counter.
229             k,          // The member key.
230             v,          // The member value.
231             length,
232             mind = gap,
233             partial,
234             value = holder[key];
235 
236 // If the value has a toJSON method, call it to obtain a replacement value.
237 
238         if (value && typeof value === 'object' &&
239                 typeof value.toJSON === 'function') {
240             value = value.toJSON(key);
241         }
242 
243 // If we were called with a replacer function, then call the replacer to
244 // obtain a replacement value.
245 
246         if (typeof rep === 'function') {
247             value = rep.call(holder, key, value);
248         }
249 
250 // What happens next depends on the value's type.
251 
252         switch (typeof value) {
253         case 'string':
254             return quote(value);
255 
256         case 'number':
257 
258 // JSON numbers must be finite. Encode non-finite numbers as null.
259 
260             return isFinite(value) ? String(value) : 'null';
261 
262         case 'boolean':
263         case 'null':
264 
265 // If the value is a boolean or null, convert it to a string. Note:
266 // typeof null does not produce 'null'. The case is included here in
267 // the remote chance that this gets fixed someday.
268 
269             return String(value);
270 
271 // If the type is 'object', we might be dealing with an object or an array or
272 // null.
273 
274         case 'object':
275 
276 // Due to a specification blunder in ECMAScript, typeof null is 'object',
277 // so watch out for that case.
278 
279             if (!value) {
280                 return 'null';
281             }
282 
283 // Make an array to hold the partial results of stringifying this object value.
284 
285             gap += indent;
286             partial = [];
287 
288 // Is the value an array?
289 
290             if (Object.prototype.toString.apply(value) === '[object Array]') {
291 
292 // The value is an array. Stringify every element. Use null as a placeholder
293 // for non-JSON values.
294 
295                 length = value.length;
296                 for (i = 0; i < length; i += 1) {
297                     partial[i] = str(i, value) || 'null';
298                 }
299 
300 // Join all of the elements together, separated with commas, and wrap them in
301 // brackets.
302 
303                 v = partial.length === 0 ? '[]' :
304                     gap ? '[\n' + gap +
305                             partial.join(',\n' + gap) + '\n' +
306                                 mind + ']' :
307                           '[' + partial.join(',') + ']';
308                 gap = mind;
309                 return v;
310             }
311 
312 // If the replacer is an array, use it to select the members to be stringified.
313 
314             if (rep && typeof rep === 'object') {
315                 length = rep.length;
316                 for (i = 0; i < length; i += 1) {
317                     k = rep[i];
318                     if (typeof k === 'string') {
319                         v = str(k, value);
320                         if (v) {
321                             partial.push(quote(k) + (gap ? ': ' : ':') + v);
322                         }
323                     }
324                 }
325             } else {
326 
327 // Otherwise, iterate through all of the keys in the object.
328 
329                 for (k in value) {
330                     if (Object.hasOwnProperty.call(value, k)) {
331                         v = str(k, value);
332                         if (v) {
333                             partial.push(quote(k) + (gap ? ': ' : ':') + v);
334                         }
335                     }
336                 }
337             }
338 
339 // Join all of the member texts together, separated with commas,
340 // and wrap them in braces.
341 
342             v = partial.length === 0 ? '{}' :
343                 gap ? '{\n' + gap + partial.join(',\n' + gap) + '\n' +
344                         mind + '}' : '{' + partial.join(',') + '}';
345             gap = mind;
346             return v;
347         }
348     }
349 
350 // If the JSON object does not yet have a stringify method, give it one.
351 
352     if (typeof JSON.stringify !== 'function') {
353         JSON.stringify = function (value, replacer, space) {
354 
355 // The stringify method takes a value and an optional replacer, and an optional
356 // space parameter, and returns a JSON text. The replacer can be a function
357 // that can replace values, or an array of strings that will select the keys.
358 // A default replacer method can be provided. Use of the space parameter can
359 // produce text that is more easily readable.
360 
361             var i;
362             gap = '';
363             indent = '';
364 
365 // If the space parameter is a number, make an indent string containing that
366 // many spaces.
367 
368             if (typeof space === 'number') {
369                 for (i = 0; i < space; i += 1) {
370                     indent += ' ';
371                 }
372 
373 // If the space parameter is a string, it will be used as the indent string.
374 
375             } else if (typeof space === 'string') {
376                 indent = space;
377             }
378 
379 // If there is a replacer, it must be a function or an array.
380 // Otherwise, throw an error.
381 
382             rep = replacer;
383             if (replacer && typeof replacer !== 'function' &&
384                     (typeof replacer !== 'object' ||
385                      typeof replacer.length !== 'number')) {
386                 throw new Error('JSON.stringify');
387             }
388 
389 // Make a fake root object containing our value under the key of ''.
390 // Return the result of stringifying the value.
391 
392             return str('', {'': value});
393         };
394     }
395 
396 
397 // If the JSON object does not yet have a parse method, give it one.
398 
399     if (typeof JSON.parse !== 'function') {
400         JSON.parse = function (text, reviver) {
401 
402 // The parse method takes a text and an optional reviver function, and returns
403 // a JavaScript value if the text is a valid JSON text.
404 
405             var j;
406 
407             function walk(holder, key) {
408 
409 // The walk method is used to recursively walk the resulting structure so
410 // that modifications can be made.
411 
412                 var k, v, value = holder[key];
413                 if (value && typeof value === 'object') {
414                     for (k in value) {
415                         if (Object.hasOwnProperty.call(value, k)) {
416                             v = walk(value, k);
417                             if (v !== undefined) {
418                                 value[k] = v;
419                             } else {
420                                 delete value[k];
421                             }
422                         }
423                     }
424                 }
425                 return reviver.call(holder, key, value);
426             }
427 
428 
429 // Parsing happens in four stages. In the first stage, we replace certain
430 // Unicode characters with escape sequences. JavaScript handles many characters
431 // incorrectly, either silently deleting them, or treating them as line endings.
432 
433             cx.lastIndex = 0;
434             if (cx.test(text)) {
435                 text = text.replace(cx, function (a) {
436                     return '\\u' +
437                         ('0000' + a.charCodeAt(0).toString(16)).slice(-4);
438                 });
439             }
440 
441 // In the second stage, we run the text against regular expressions that look
442 // for non-JSON patterns. We are especially concerned with '()' and 'new'
443 // because they can cause invocation, and '=' because it can cause mutation.
444 // But just to be safe, we want to reject all unexpected forms.
445 
446 // We split the second stage into 4 regexp operations in order to work around
447 // crippling inefficiencies in IE's and Safari's regexp engines. First we
448 // replace the JSON backslash pairs with '@' (a non-JSON character). Second, we
449 // replace all simple value tokens with ']' characters. Third, we delete all
450 // open brackets that follow a colon or comma or that begin the text. Finally,
451 // we look to see that the remaining characters are only whitespace or ']' or
452 // ',' or ':' or '{' or '}'. If that is so, then the text is safe for eval.
453 
454             if (/^[\],:{}\s]*$/.
455 test(text.replace(/\\(?:["\\\/bfnrt]|u[0-9a-fA-F]{4})/g, '@').
456 replace(/"[^"\\\n\r]*"|true|false|null|-?\d+(?:\.\d*)?(?:[eE][+\-]?\d+)?/g, ']').
457 replace(/(?:^|:|,)(?:\s*\[)+/g, ''))) {
458 
459 // In the third stage we use the eval function to compile the text into a
460 // JavaScript structure. The '{' operator is subject to a syntactic ambiguity
461 // in JavaScript: it can begin a block or an object literal. We wrap the text
462 // in parens to eliminate the ambiguity.
463 
464                 j = eval('(' + text + ')');
465 
466 // In the optional fourth stage, we recursively walk the new structure, passing
467 // each name/value pair to a reviver function for possible transformation.
468 
469                 return typeof reviver === 'function' ?
470                     walk({'': j}, '') : j;
471             }
472 
473 // If the text is not JSON parseable, then a SyntaxError is thrown.
474 
475             throw new SyntaxError('JSON.parse');
476         };
477     }
478 })();
479