1/*
2    json2.js
3    2013-05-26
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
12    This code should be minified before deployment.
13    See http://javascript.crockford.com/jsmin.html
14
15    USE YOUR OWN COPY. IT IS EXTREMELY UNWISE TO LOAD CODE FROM SERVERS YOU DO
16    NOT CONTROL.
17
18
19    This file creates a global JSON object containing two methods: stringify
20    and parse.
21
22        JSON.stringify(value, replacer, space)
23            value       any JavaScript value, usually an object or array.
24
25            replacer    an optional parameter that determines how object
26                        values are stringified for objects. It can be a
27                        function or an array of strings.
28
29            space       an optional parameter that specifies the indentation
30                        of nested structures. If it is omitted, the text will
31                        be packed without extra whitespace. If it is a number,
32                        it will specify the number of spaces to indent at each
33                        level. If it is a string (such as '\t' or ' '),
34                        it contains the characters used to indent at each level.
35
36            This method produces a JSON text from a JavaScript value.
37
38            When an object value is found, if the object contains a toJSON
39            method, its toJSON method will be called and the result will be
40            stringified. A toJSON method does not serialize: it returns the
41            value represented by the name/value pair that should be serialized,
42            or undefined if nothing should be serialized. The toJSON method
43            will be passed the key associated with the value, and this will be
44            bound to the value
45
46            For example, this would serialize Dates as ISO strings.
47
48                Date.prototype.toJSON = function (key) {
49                    function f(n) {
50                        // Format integers to have at least two digits.
51                        return n < 10 ? '0' + n : n;
52                    }
53
54                    return this.getUTCFullYear()   + '-' +
55                         f(this.getUTCMonth() + 1) + '-' +
56                         f(this.getUTCDate())      + 'T' +
57                         f(this.getUTCHours())     + ':' +
58                         f(this.getUTCMinutes())   + ':' +
59                         f(this.getUTCSeconds())   + 'Z';
60                };
61
62            You can provide an optional replacer method. It will be passed the
63            key and value of each member, with this bound to the containing
64            object. The value that is returned from your method will be
65            serialized. If your method returns undefined, then the member will
66            be excluded from the serialization.
67
68            If the replacer parameter is an array of strings, then it will be
69            used to select the members to be serialized. It filters the results
70            such that only members with keys listed in the replacer array are
71            stringified.
72
73            Values that do not have JSON representations, such as undefined or
74            functions, will not be serialized. Such values in objects will be
75            dropped; in arrays they will be replaced with null. You can use
76            a replacer function to replace those with JSON values.
77            JSON.stringify(undefined) returns undefined.
78
79            The optional space parameter produces a stringification of the
80            value that is filled with line breaks and indentation to make it
81            easier to read.
82
83            If the space parameter is a non-empty string, then that string will
84            be used for indentation. If the space parameter is a number, then
85            the indentation will be that many spaces.
86
87            Example:
88
89            text = JSON.stringify(['e', {pluribus: 'unum'}]);
90            // text is '["e",{"pluribus":"unum"}]'
91
92
93            text = JSON.stringify(['e', {pluribus: 'unum'}], null, '\t');
94            // text is '[\n\t"e",\n\t{\n\t\t"pluribus": "unum"\n\t}\n]'
95
96            text = JSON.stringify([new Date()], function (key, value) {
97                return this[key] instanceof Date ?
98                    'Date(' + this[key] + ')' : value;
99            });
100            // text is '["Date(---current time---)"]'
101
102
103        JSON.parse(text, reviver)
104            This method parses a JSON text to produce an object or array.
105            It can throw a SyntaxError exception.
106
107            The optional reviver parameter is a function that can filter and
108            transform the results. It receives each of the keys and values,
109            and its return value is used instead of the original value.
110            If it returns what it received, then the structure is not modified.
111            If it returns undefined then the member is deleted.
112
113            Example:
114
115            // Parse the text. Values that look like ISO date strings will
116            // be converted to Date objects.
117
118            myData = JSON.parse(text, function (key, value) {
119                var a;
120                if (typeof value === 'string') {
121                    a =
122/^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2}(?:\.\d*)?)Z$/.exec(value);
123                    if (a) {
124                        return new Date(Date.UTC(+a[1], +a[2] - 1, +a[3], +a[4],
125                            +a[5], +a[6]));
126                    }
127                }
128                return value;
129            });
130
131            myData = JSON.parse('["Date(09/09/2001)"]', function (key, value) {
132                var d;
133                if (typeof value === 'string' &&
134                        value.slice(0, 5) === 'Date(' &&
135                        value.slice(-1) === ')') {
136                    d = new Date(value.slice(5, -1));
137                    if (d) {
138                        return d;
139                    }
140                }
141                return value;
142            });
143
144
145    This is a reference implementation. You are free to copy, modify, or
146    redistribute.
147*/
148
149/*jslint evil: true, regexp: true */
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
159// Create a JSON object only if one does not already exist. We create the
160// methods in a closure to avoid creating global variables.
161
162if (typeof JSON !== 'object') {
163    JSON = {};
164}
165
166(function () {
167    'use strict';
168
169    function f(n) {
170        // Format integers to have at least two digits.
171        return n < 10 ? '0' + n : n;
172    }
173
174    if (typeof Date.prototype.toJSON !== 'function') {
175
176        Date.prototype.toJSON = function () {
177
178            return isFinite(this.valueOf())
179                ? this.getUTCFullYear()     + '-' +
180                    f(this.getUTCMonth() + 1) + '-' +
181                    f(this.getUTCDate())      + 'T' +
182                    f(this.getUTCHours())     + ':' +
183                    f(this.getUTCMinutes())   + ':' +
184                    f(this.getUTCSeconds())   + 'Z'
185                : null;
186        };
187
188        String.prototype.toJSON      =
189            Number.prototype.toJSON  =
190            Boolean.prototype.toJSON = function () {
191                return this.valueOf();
192            };
193    }
194
195    var cx = /[\u0000\u00ad\u0600-\u0604\u070f\u17b4\u17b5\u200c-\u200f\u2028-\u202f\u2060-\u206f\ufeff\ufff0-\uffff]/g,
196        escapable = /[\\\"\x00-\x1f\x7f-\x9f\u00ad\u0600-\u0604\u070f\u17b4\u17b5\u200c-\u200f\u2028-\u202f\u2060-\u206f\ufeff\ufff0-\uffff]/g,
197        gap,
198        indent,
199        meta = {    // table of character substitutions
200            '\b': '\\b',
201            '\t': '\\t',
202            '\n': '\\n',
203            '\f': '\\f',
204            '\r': '\\r',
205            '"' : '\\"',
206            '\\': '\\\\'
207        },
208        rep;
209
210
211    function quote(string) {
212
213// If the string contains no control characters, no quote characters, and no
214// backslash characters, then we can safely slap some quotes around it.
215// Otherwise we must also replace the offending characters with safe escape
216// sequences.
217
218        escapable.lastIndex = 0;
219        return escapable.test(string) ? '"' + string.replace(escapable, function (a) {
220            var c = meta[a];
221            return typeof c === 'string'
222                ? c
223                : '\\u' + ('0000' + a.charCodeAt(0).toString(16)).slice(-4);
224        }) + '"' : '"' + string + '"';
225    }
226
227
228    function str(key, holder) {
229
230// Produce a string from holder[key].
231
232        var i,          // The loop counter.
233            k,          // The member key.
234            v,          // The member value.
235            length,
236            mind = gap,
237            partial,
238            value = holder[key];
239
240// If the value has a toJSON method, call it to obtain a replacement value.
241
242        if (value && typeof value === 'object' &&
243                typeof value.toJSON === 'function') {
244            value = value.toJSON(key);
245        }
246
247// If we were called with a replacer function, then call the replacer to
248// obtain a replacement value.
249
250        if (typeof rep === 'function') {
251            value = rep.call(holder, key, value);
252        }
253
254// What happens next depends on the value's type.
255
256        switch (typeof value) {
257        case 'string':
258            return quote(value);
259
260        case 'number':
261
262// JSON numbers must be finite. Encode non-finite numbers as null.
263
264            return isFinite(value) ? String(value) : 'null';
265
266        case 'boolean':
267        case 'null':
268
269// If the value is a boolean or null, convert it to a string. Note:
270// typeof null does not produce 'null'. The case is included here in
271// the remote chance that this gets fixed someday.
272
273            return String(value);
274
275// If the type is 'object', we might be dealing with an object or an array or
276// null.
277
278        case 'object':
279
280// Due to a specification blunder in ECMAScript, typeof null is 'object',
281// so watch out for that case.
282
283            if (!value) {
284                return 'null';
285            }
286
287// Make an array to hold the partial results of stringifying this object value.
288
289            gap += indent;
290            partial = [];
291
292// Is the value an array?
293
294            if (Object.prototype.toString.apply(value) === '[object Array]') {
295
296// The value is an array. Stringify every element. Use null as a placeholder
297// for non-JSON values.
298
299                length = value.length;
300                for (i = 0; i < length; i += 1) {
301                    partial[i] = str(i, value) || 'null';
302                }
303
304// Join all of the elements together, separated with commas, and wrap them in
305// brackets.
306
307                v = partial.length === 0
308                    ? '[]'
309                    : gap
310                    ? '[\n' + gap + partial.join(',\n' + gap) + '\n' + mind + ']'
311                    : '[' + partial.join(',') + ']';
312                gap = mind;
313                return v;
314            }
315
316// If the replacer is an array, use it to select the members to be stringified.
317
318            if (rep && typeof rep === 'object') {
319                length = rep.length;
320                for (i = 0; i < length; i += 1) {
321                    if (typeof rep[i] === 'string') {
322                        k = rep[i];
323                        v = str(k, value);
324                        if (v) {
325                            partial.push(quote(k) + (gap ? ': ' : ':') + v);
326                        }
327                    }
328                }
329            } else {
330
331// Otherwise, iterate through all of the keys in the object.
332
333                for (k in value) {
334                    if (Object.prototype.hasOwnProperty.call(value, k)) {
335                        v = str(k, value);
336                        if (v) {
337                            partial.push(quote(k) + (gap ? ': ' : ':') + v);
338                        }
339                    }
340                }
341            }
342
343// Join all of the member texts together, separated with commas,
344// and wrap them in braces.
345
346            v = partial.length === 0
347                ? '{}'
348                : gap
349                ? '{\n' + gap + partial.join(',\n' + gap) + '\n' + mind + '}'
350                : '{' + partial.join(',') + '}';
351            gap = mind;
352            return v;
353        }
354    }
355
356// If the JSON object does not yet have a stringify method, give it one.
357
358    if (typeof JSON.stringify !== 'function') {
359        JSON.stringify = function (value, replacer, space) {
360
361// The stringify method takes a value and an optional replacer, and an optional
362// space parameter, and returns a JSON text. The replacer can be a function
363// that can replace values, or an array of strings that will select the keys.
364// A default replacer method can be provided. Use of the space parameter can
365// produce text that is more easily readable.
366
367            var i;
368            gap = '';
369            indent = '';
370
371// If the space parameter is a number, make an indent string containing that
372// many spaces.
373
374            if (typeof space === 'number') {
375                for (i = 0; i < space; i += 1) {
376                    indent += ' ';
377                }
378
379// If the space parameter is a string, it will be used as the indent string.
380
381            } else if (typeof space === 'string') {
382                indent = space;
383            }
384
385// If there is a replacer, it must be a function or an array.
386// Otherwise, throw an error.
387
388            rep = replacer;
389            if (replacer && typeof replacer !== 'function' &&
390                    (typeof replacer !== 'object' ||
391                    typeof replacer.length !== 'number')) {
392                throw new Error('JSON.stringify');
393            }
394
395// Make a fake root object containing our value under the key of ''.
396// Return the result of stringifying the value.
397
398            return str('', {'': value});
399        };
400    }
401
402
403// If the JSON object does not yet have a parse method, give it one.
404
405    if (typeof JSON.parse !== 'function') {
406        JSON.parse = function (text, reviver) {
407
408// The parse method takes a text and an optional reviver function, and returns
409// a JavaScript value if the text is a valid JSON text.
410
411            var j;
412
413            function walk(holder, key) {
414
415// The walk method is used to recursively walk the resulting structure so
416// that modifications can be made.
417
418                var k, v, value = holder[key];
419                if (value && typeof value === 'object') {
420                    for (k in value) {
421                        if (Object.prototype.hasOwnProperty.call(value, k)) {
422                            v = walk(value, k);
423                            if (v !== undefined) {
424                                value[k] = v;
425                            } else {
426                                delete value[k];
427                            }
428                        }
429                    }
430                }
431                return reviver.call(holder, key, value);
432            }
433
434
435// Parsing happens in four stages. In the first stage, we replace certain
436// Unicode characters with escape sequences. JavaScript handles many characters
437// incorrectly, either silently deleting them, or treating them as line endings.
438
439            text = String(text);
440            cx.lastIndex = 0;
441            if (cx.test(text)) {
442                text = text.replace(cx, function (a) {
443                    return '\\u' +
444                        ('0000' + a.charCodeAt(0).toString(16)).slice(-4);
445                });
446            }
447
448// In the second stage, we run the text against regular expressions that look
449// for non-JSON patterns. We are especially concerned with '()' and 'new'
450// because they can cause invocation, and '=' because it can cause mutation.
451// But just to be safe, we want to reject all unexpected forms.
452
453// We split the second stage into 4 regexp operations in order to work around
454// crippling inefficiencies in IE's and Safari's regexp engines. First we
455// replace the JSON backslash pairs with '@' (a non-JSON character). Second, we
456// replace all simple value tokens with ']' characters. Third, we delete all
457// open brackets that follow a colon or comma or that begin the text. Finally,
458// we look to see that the remaining characters are only whitespace or ']' or
459// ',' or ':' or '{' or '}'. If that is so, then the text is safe for eval.
460
461            if (/^[\],:{}\s]*$/
462                    .test(text.replace(/\\(?:["\\\/bfnrt]|u[0-9a-fA-F]{4})/g, '@')
463                        .replace(/"[^"\\\n\r]*"|true|false|null|-?\d+(?:\.\d*)?(?:[eE][+\-]?\d+)?/g, ']')
464                        .replace(/(?:^|:|,)(?:\s*\[)+/g, ''))) {
465
466// In the third stage we use the eval function to compile the text into a
467// JavaScript structure. The '{' operator is subject to a syntactic ambiguity
468// in JavaScript: it can begin a block or an object literal. We wrap the text
469// in parens to eliminate the ambiguity.
470
471                j = eval('(' + text + ')');
472
473// In the optional fourth stage, we recursively walk the new structure, passing
474// each name/value pair to a reviver function for possible transformation.
475
476                return typeof reviver === 'function'
477                    ? walk({'': j}, '')
478                    : j;
479            }
480
481// If the text is not JSON parseable, then a SyntaxError is thrown.
482
483            throw new SyntaxError('JSON.parse');
484        };
485    }
486}());
487