json2-es5-compat.js revision cfb0617749a64f2e177386b030d46007b8c4b179
1/*
2    http://www.JSON.org/json2.js
3    2009-04-16
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
161if (!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
184    var cx = /[\u0000\u00ad\u0600-\u0604\u070f\u17b4\u17b5\u200c-\u200f\u2028-\u202f\u2060-\u206f\ufeff\ufff0-\uffff]/g,
185        escapable = /[\\\"\x00-\x1f]/g,
186        gap,
187        indent,
188        meta = {    // table of character substitutions
189            '\b': '\\b',
190            '\t': '\\t',
191            '\n': '\\n',
192            '\f': '\\f',
193            '\r': '\\r',
194            '"' : '\\"',
195            '\\': '\\\\'
196        },
197        rep;
198
199
200    function quote(string) {
201
202// If the string contains no control characters, no quote characters, and no
203// backslash characters, then we can safely slap some quotes around it.
204// Otherwise we must also replace the offending characters with safe escape
205// sequences.
206
207        escapable.lastIndex = 0;
208        return escapable.test(string) ?
209            '"' + string.replace(escapable, function (a) {
210                var c = meta[a];
211                return typeof c === 'string' ? c :
212                    '\\u' + ('0000' + a.charCodeAt(0).toString(16)).slice(-4);
213            }) + '"' :
214            '"' + string + '"';
215    }
216
217
218    function str(key, holder) {
219
220// Produce a string from holder[key].
221
222        var i,          // The loop counter.
223            k,          // The member key.
224            v,          // The member value.
225            length,
226            mind = gap,
227            partial,
228            value = holder[key];
229
230// If the value has a toJSON method, call it to obtain a replacement value.
231
232        if (value && typeof value === 'object' &&
233                typeof value.toJSON === 'function') {
234            value = value.toJSON(key);
235        }
236
237// If we were called with a replacer function, then call the replacer to
238// obtain a replacement value.
239
240        if (typeof rep === 'function') {
241            value = rep.call(holder, key, value);
242        }
243
244// What happens next depends on the value's type.
245
246        if (value && ((typeof value) === "object")) {
247            if (value.constructor === String || value.constructor === Number || value.constructor === Boolean)
248                value = value.valueOf();
249        }
250
251        switch (typeof value) {
252        case 'string':
253            return quote(value);
254
255        case 'number':
256
257// JSON numbers must be finite. Encode non-finite numbers as null.
258
259            return isFinite(value) ? String(value) : 'null';
260
261        case 'boolean':
262        case 'null':
263
264// If the value is a boolean or null, convert it to a string. Note:
265// typeof null does not produce 'null'. The case is included here in
266// the remote chance that this gets fixed someday.
267
268            return String(value);
269
270// If the type is 'object', we might be dealing with an object or an array or
271// null.
272
273        case 'object':
274
275// Due to a specification blunder in ECMAScript, typeof null is 'object',
276// so watch out for that case.
277
278            if (!value) {
279                return 'null';
280            }
281
282// Make an array to hold the partial results of stringifying this object value.
283
284            gap += indent;
285            partial = [];
286
287// Is the value an array?
288
289            if (Object.prototype.toString.apply(value) === '[object Array]') {
290
291// The value is an array. Stringify every element. Use null as a placeholder
292// for non-JSON values.
293
294                length = value.length;
295                for (i = 0; i < length; i += 1) {
296                    partial[i] = str(i, value) || 'null';
297                }
298
299// Join all of the elements together, separated with commas, and wrap them in
300// brackets.
301
302                v = partial.length === 0 ? '[]' :
303                    gap ? '[\n' + gap +
304                            partial.join(',\n' + gap) + '\n' +
305                                mind + ']' :
306                          '[' + partial.join(',') + ']';
307                gap = mind;
308                return v;
309            }
310
311// If the replacer is an array, use it to select the members to be stringified.
312
313            if (rep && typeof rep === 'object') {
314                length = rep.length;
315                for (i = 0; i < length; i += 1) {
316                    k = rep[i];
317                    if (typeof k === 'string') {
318                        v = str(k, value);
319                        if (v) {
320                            partial.push(quote(k) + (gap ? ': ' : ':') + v);
321                        }
322                    }
323                }
324            } else {
325
326// Otherwise, iterate through all of the keys in the object.
327
328                for (k in value) {
329                    if (Object.hasOwnProperty.call(value, k)) {
330                        v = str(k, value);
331                        if (v) {
332                            partial.push(quote(k) + (gap ? ': ' : ':') + v);
333                        }
334                    }
335                }
336            }
337
338// Join all of the member texts together, separated with commas,
339// and wrap them in braces.
340
341            v = partial.length === 0 ? '{}' :
342                gap ? '{\n' + gap + partial.join(',\n' + gap) + '\n' +
343                        mind + '}' : '{' + partial.join(',') + '}';
344            gap = mind;
345            return v;
346        }
347    }
348
349// If the JSON object does not yet have a stringify method, give it one.
350
351    if (typeof JSON.stringify !== 'function') {
352        JSON.stringify = function (value, replacer, space) {
353
354// The stringify method takes a value and an optional replacer, and an optional
355// space parameter, and returns a JSON text. The replacer can be a function
356// that can replace values, or an array of strings that will select the keys.
357// A default replacer method can be provided. Use of the space parameter can
358// produce text that is more easily readable.
359
360            var i;
361            gap = '';
362            indent = '';
363
364// If the space parameter is a number, make an indent string containing that
365// many spaces.
366
367            if (typeof space === 'number') {
368                for (i = 0; i < space; i += 1) {
369                    indent += ' ';
370                }
371
372// If the space parameter is a string, it will be used as the indent string.
373
374            } else if (typeof space === 'string') {
375                indent = space;
376            }
377
378// If there is a replacer, it must be a function or an array.
379// Otherwise, throw an error.
380
381            rep = replacer;
382            if (replacer && typeof replacer !== 'function' &&
383                    (typeof replacer !== 'object' ||
384                     typeof replacer.length !== 'number')) {
385                throw new Error('JSON.stringify');
386            }
387
388// Make a fake root object containing our value under the key of ''.
389// Return the result of stringifying the value.
390
391            return str('', {'': value});
392        };
393    }
394
395
396// If the JSON object does not yet have a parse method, give it one.
397
398    if (typeof JSON.parse !== 'function') {
399        JSON.parse = function (text, reviver) {
400
401// The parse method takes a text and an optional reviver function, and returns
402// a JavaScript value if the text is a valid JSON text.
403
404            var j;
405
406            function walk(holder, key) {
407
408// The walk method is used to recursively walk the resulting structure so
409// that modifications can be made.
410
411                var k, v, value = holder[key];
412                if (value && typeof value === 'object') {
413                    for (k in value) {
414                        if (Object.hasOwnProperty.call(value, k)) {
415                            v = walk(value, k);
416                            if (v !== undefined) {
417                                value[k] = v;
418                            } else {
419                                delete value[k];
420                            }
421                        }
422                    }
423                }
424                return reviver.call(holder, key, value);
425            }
426
427
428// Parsing happens in four stages. In the first stage, we replace certain
429// Unicode characters with escape sequences. JavaScript handles many characters
430// incorrectly, either silently deleting them, or treating them as line endings.
431
432            cx.lastIndex = 0;
433            if (cx.test(text)) {
434                text = text.replace(cx, function (a) {
435                    return '\\u' +
436                        ('0000' + a.charCodeAt(0).toString(16)).slice(-4);
437                });
438            }
439
440// In the second stage, we run the text against regular expressions that look
441// for non-JSON patterns. We are especially concerned with '()' and 'new'
442// because they can cause invocation, and '=' because it can cause mutation.
443// But just to be safe, we want to reject all unexpected forms.
444
445// We split the second stage into 4 regexp operations in order to work around
446// crippling inefficiencies in IE's and Safari's regexp engines. First we
447// replace the JSON backslash pairs with '@' (a non-JSON character). Second, we
448// replace all simple value tokens with ']' characters. Third, we delete all
449// open brackets that follow a colon or comma or that begin the text. Finally,
450// we look to see that the remaining characters are only whitespace or ']' or
451// ',' or ':' or '{' or '}'. If that is so, then the text is safe for eval.
452
453            if (/^[\],:{}\s]*$/.
454test(text.replace(/\\(?:["\\\/bfnrt]|u[0-9a-fA-F]{4})/g, '@').
455replace(/"[^"\\\n\r]*"|true|false|null|-?\d+(?:\.\d*)?(?:[eE][+\-]?\d+)?/g, ']').
456replace(/(?:^|:|,)(?:\s*\[)+/g, ''))) {
457
458// In the third stage we use the eval function to compile the text into a
459// JavaScript structure. The '{' operator is subject to a syntactic ambiguity
460// in JavaScript: it can begin a block or an object literal. We wrap the text
461// in parens to eliminate the ambiguity.
462
463                j = eval('(' + text + ')');
464
465// In the optional fourth stage, we recursively walk the new structure, passing
466// each name/value pair to a reviver function for possible transformation.
467
468                return typeof reviver === 'function' ?
469                    walk({'': j}, '') : j;
470            }
471
472// If the text is not JSON parseable, then a SyntaxError is thrown.
473
474            throw new SyntaxError('JSON.parse');
475        };
476    }
477}());
478