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1/*
2 json2.js
3 2014-02-04
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,
196 escapable,
197 gap,
198 indent,
199 meta,
200 rep;
201
202
203 function quote(string) {
204
205// If the string contains no control characters, no quote characters, and no
206// backslash characters, then we can safely slap some quotes around it.
207// Otherwise we must also replace the offending characters with safe escape
208// sequences.
209
210 escapable.lastIndex = 0;
211 return escapable.test(string) ? '"' + string.replace(escapable, function (a) {
212 var c = meta[a];
213 return typeof c === 'string'
214 ? c
215 : '\\u' + ('0000' + a.charCodeAt(0).toString(16)).slice(-4);
216 }) + '"' : '"' + string + '"';
217 }
218
219
220 function str(key, holder) {
221
222// Produce a string from holder[key].
223
224 var i, // The loop counter.
225 k, // The member key.
226 v, // The member value.
227 length,
228 mind = gap,
229 partial,
230 value = holder[key];
231
232// If the value has a toJSON method, call it to obtain a replacement value.
233
234 if (value && typeof value === 'object' &&
235 typeof value.toJSON === 'function') {
236 value = value.toJSON(key);
237 }
238
239// If we were called with a replacer function, then call the replacer to
240// obtain a replacement value.
241
242 if (typeof rep === 'function') {
243 value = rep.call(holder, key, value);
244 }
245
246// What happens next depends on the value's type.
247
248 switch (typeof value) {
249 case 'string':
250 return quote(value);
251
252 case 'number':
253
254// JSON numbers must be finite. Encode non-finite numbers as null.
255
256 return isFinite(value) ? String(value) : 'null';
257
258 case 'boolean':
259 case 'null':
260
261// If the value is a boolean or null, convert it to a string. Note:
262// typeof null does not produce 'null'. The case is included here in
263// the remote chance that this gets fixed someday.
264
265 return String(value);
266
267// If the type is 'object', we might be dealing with an object or an array or
268// null.
269
270 case 'object':
271
272// Due to a specification blunder in ECMAScript, typeof null is 'object',
273// so watch out for that case.
274
275 if (!value) {
276 return 'null';
277 }
278
279// Make an array to hold the partial results of stringifying this object value.
280
281 gap += indent;
282 partial = [];
283
284// Is the value an array?
285
286 if (Object.prototype.toString.apply(value) === '[object Array]') {
287
288// The value is an array. Stringify every element. Use null as a placeholder
289// for non-JSON values.
290
291 length = value.length;
292 for (i = 0; i < length; i += 1) {
293 partial[i] = str(i, value) || 'null';
294 }
295
296// Join all of the elements together, separated with commas, and wrap them in
297// brackets.
298
299 v = partial.length === 0
300 ? '[]'
301 : gap
302 ? '[\n' + gap + partial.join(',\n' + gap) + '\n' + mind + ']'
303 : '[' + partial.join(',') + ']';
304 gap = mind;
305 return v;
306 }
307
308// If the replacer is an array, use it to select the members to be stringified.
309
310 if (rep && typeof rep === 'object') {
311 length = rep.length;
312 for (i = 0; i < length; i += 1) {
313 if (typeof rep[i] === 'string') {
314 k = rep[i];
315 v = str(k, value);
316 if (v) {
317 partial.push(quote(k) + (gap ? ': ' : ':') + v);
318 }
319 }
320 }
321 } else {
322
323// Otherwise, iterate through all of the keys in the object.
324
325 for (k in value) {
326 if (Object.prototype.hasOwnProperty.call(value, k)) {
327 v = str(k, value);
328 if (v) {
329 partial.push(quote(k) + (gap ? ': ' : ':') + v);
330 }
331 }
332 }
333 }
334
335// Join all of the member texts together, separated with commas,
336// and wrap them in braces.
337
338 v = partial.length === 0
339 ? '{}'
340 : gap
341 ? '{\n' + gap + partial.join(',\n' + gap) + '\n' + mind + '}'
342 : '{' + partial.join(',') + '}';
343 gap = mind;
344 return v;
345 }
346 }
347
348// If the JSON object does not yet have a stringify method, give it one.
349
350 if (typeof JSON.stringify !== 'function') {
351 escapable = /[\\\"\x00-\x1f\x7f-\x9f\u00ad\u0600-\u0604\u070f\u17b4\u17b5\u200c-\u200f\u2028-\u202f\u2060-\u206f\ufeff\ufff0-\uffff]/g;
352 meta = { // table of character substitutions
353 '\b': '\\b',
354 '\t': '\\t',
355 '\n': '\\n',
356 '\f': '\\f',
357 '\r': '\\r',
358 '"' : '\\"',
359 '\\': '\\\\'
360 };
361 JSON.stringify = function (value, replacer, space) {
362
363// The stringify method takes a value and an optional replacer, and an optional
364// space parameter, and returns a JSON text. The replacer can be a function
365// that can replace values, or an array of strings that will select the keys.
366// A default replacer method can be provided. Use of the space parameter can
367// produce text that is more easily readable.
368
369 var i;
370 gap = '';
371 indent = '';
372
373// If the space parameter is a number, make an indent string containing that
374// many spaces.
375
376 if (typeof space === 'number') {
377 for (i = 0; i < space; i += 1) {
378 indent += ' ';
379 }
380
381// If the space parameter is a string, it will be used as the indent string.
382
383 } else if (typeof space === 'string') {
384 indent = space;
385 }
386
387// If there is a replacer, it must be a function or an array.
388// Otherwise, throw an error.
389
390 rep = replacer;
391 if (replacer && typeof replacer !== 'function' &&
392 (typeof replacer !== 'object' ||
393 typeof replacer.length !== 'number')) {
394 throw new Error('JSON.stringify');
395 }
396
397// Make a fake root object containing our value under the key of ''.
398// Return the result of stringifying the value.
399
400 return str('', {'': value});
401 };
402 }
403
404
405// If the JSON object does not yet have a parse method, give it one.
406
407 if (typeof JSON.parse !== 'function') {
408 cx = /[\u0000\u00ad\u0600-\u0604\u070f\u17b4\u17b5\u200c-\u200f\u2028-\u202f\u2060-\u206f\ufeff\ufff0-\uffff]/g;
409 JSON.parse = function (text, reviver) {
410
411// The parse method takes a text and an optional reviver function, and returns
412// a JavaScript value if the text is a valid JSON text.
413
414 var j;
415
416 function walk(holder, key) {
417
418// The walk method is used to recursively walk the resulting structure so
419// that modifications can be made.
420
421 var k, v, value = holder[key];
422 if (value && typeof value === 'object') {
423 for (k in value) {
424 if (Object.prototype.hasOwnProperty.call(value, k)) {
425 v = walk(value, k);
426 if (v !== undefined) {
427 value[k] = v;
428 } else {
429 delete value[k];
430 }
431 }
432 }
433 }
434 return reviver.call(holder, key, value);
435 }
436
437
438// Parsing happens in four stages. In the first stage, we replace certain
439// Unicode characters with escape sequences. JavaScript handles many characters
440// incorrectly, either silently deleting them, or treating them as line endings.
441
442 text = String(text);
443 cx.lastIndex = 0;
444 if (cx.test(text)) {
445 text = text.replace(cx, function (a) {
446 return '\\u' +
447 ('0000' + a.charCodeAt(0).toString(16)).slice(-4);
448 });
449 }
450
451// In the second stage, we run the text against regular expressions that look
452// for non-JSON patterns. We are especially concerned with '()' and 'new'
453// because they can cause invocation, and '=' because it can cause mutation.
454// But just to be safe, we want to reject all unexpected forms.
455
456// We split the second stage into 4 regexp operations in order to work around
457// crippling inefficiencies in IE's and Safari's regexp engines. First we
458// replace the JSON backslash pairs with '@' (a non-JSON character). Second, we
459// replace all simple value tokens with ']' characters. Third, we delete all
460// open brackets that follow a colon or comma or that begin the text. Finally,
461// we look to see that the remaining characters are only whitespace or ']' or
462// ',' or ':' or '{' or '}'. If that is so, then the text is safe for eval.
463
464 if (/^[\],:{}\s]*$/
465 .test(text.replace(/\\(?:["\\\/bfnrt]|u[0-9a-fA-F]{4})/g, '@')
466 .replace(/"[^"\\\n\r]*"|true|false|null|-?\d+(?:\.\d*)?(?:[eE][+\-]?\d+)?/g, ']')
467 .replace(/(?:^|:|,)(?:\s*\[)+/g, ''))) {
468
469// In the third stage we use the eval function to compile the text into a
470// JavaScript structure. The '{' operator is subject to a syntactic ambiguity
471// in JavaScript: it can begin a block or an object literal. We wrap the text
472// in parens to eliminate the ambiguity.
473
474 j = eval('(' + text + ')');
475
476// In the optional fourth stage, we recursively walk the new structure, passing
477// each name/value pair to a reviver function for possible transformation.
478
479 return typeof reviver === 'function'
480 ? walk({'': j}, '')
481 : j;
482 }
483
484// If the text is not JSON parseable, then a SyntaxError is thrown.
485
486 throw new SyntaxError('JSON.parse');
487 };
488 }
489}());