[ViewVC] Diff of: cvs/JSON-XS/XS.pm

Comparing JSON-XS/XS.pm (file contents):
Revision 1.9 by root, Fri Mar 23 16:00:19 2007 UTC vs.
Revision 1.20 by root, Sun Mar 25 00:47:42 2007 UTC

…		…
3	JSON::XS - JSON serialising/deserialising, done correctly and fast	3	JSON::XS - JSON serialising/deserialising, done correctly and fast
4		4
5	=head1 SYNOPSIS	5	=head1 SYNOPSIS
6		6
7	use JSON::XS;	7	use JSON::XS;
		8
		9	# exported functions, croak on error
		10
		11	$utf8_encoded_json_text = to_json $perl_hash_or_arrayref;
		12	$perl_hash_or_arrayref = from_json $utf8_encoded_json_text;
		13
		14	# oo-interface
		15
		16	$coder = JSON::XS->new->ascii->pretty->allow_nonref;
		17	$pretty_printed_unencoded = $coder->encode ($perl_scalar);
		18	$perl_scalar = $coder->decode ($unicode_json_text);
8		19
9	=head1 DESCRIPTION	20	=head1 DESCRIPTION
10		21
11	This module converts Perl data structures to JSON and vice versa. Its	22	This module converts Perl data structures to JSON and vice versa. Its
12	primary goal is to be I<correct> and its secondary goal is to be	23	primary goal is to be I<correct> and its secondary goal is to be
…		…
18	their maintainers are unresponsive, gone missing, or not listening to bug	29	their maintainers are unresponsive, gone missing, or not listening to bug
19	reports for other reasons.	30	reports for other reasons.
20		31
21	See COMPARISON, below, for a comparison to some other JSON modules.	32	See COMPARISON, below, for a comparison to some other JSON modules.
22		33
		34	See MAPPING, below, on how JSON::XS maps perl values to JSON values and
		35	vice versa.
		36
23	=head2 FEATURES	37	=head2 FEATURES
24		38
25	=over 4	39	=over 4
26		40
27	=item * correct handling of unicode issues	41	=item * correct handling of unicode issues
28		42
29	This module knows how to handle Unicode, and even documents how it does so.	43	This module knows how to handle Unicode, and even documents how and when
		44	it does so.
30		45
31	=item * round-trip integrity	46	=item * round-trip integrity
32		47
33	When you serialise a perl data structure using only datatypes supported	48	When you serialise a perl data structure using only datatypes supported
34	by JSON, the deserialised data structure is identical on the Perl level.	49	by JSON, the deserialised data structure is identical on the Perl level.
35	(e.g. the string "2.0" doesn't suddenly become "2").	50	(e.g. the string "2.0" doesn't suddenly become "2").
36		51
37	=item * strict checking of JSON correctness	52	=item * strict checking of JSON correctness
38		53
39	There is no guessing, no generating of illegal JSON strings by default,	54	There is no guessing, no generating of illegal JSON texts by default,
40	and only JSON is accepted as input (the latter is a security feature).	55	and only JSON is accepted as input by default (the latter is a security
		56	feature).
41		57
42	=item * fast	58	=item * fast
43		59
44	compared to other JSON modules, this module compares favourably.	60	Compared to other JSON modules, this module compares favourably in terms
		61	of speed, too.
45		62
46	=item * simple to use	63	=item * simple to use
47		64
48	This module has both a simple functional interface as well as an OO	65	This module has both a simple functional interface as well as an OO
49	interface.	66	interface.
50		67
51	=item * reasonably versatile output formats	68	=item * reasonably versatile output formats
52		69
53	You can choose between the most compact format possible, a pure-ascii	70	You can choose between the most compact guarenteed single-line format
54	format, or a pretty-printed format. Or you can combine those features in	71	possible (nice for simple line-based protocols), a pure-ascii format (for
		72	when your transport is not 8-bit clean), or a pretty-printed format (for
		73	when you want to read that stuff). Or you can combine those features in
55	whatever way you like.	74	whatever way you like.
56		75
57	=back	76	=back
58		77
59	=cut	78	=cut
60		79
61	package JSON::XS;	80	package JSON::XS;
62		81
		82	use strict;
		83
63	BEGIN {	84	BEGIN {
64	$VERSION = '0.3';	85	our $VERSION = '0.7';
65	@ISA = qw(Exporter);	86	our @ISA = qw(Exporter);
66		87
67	@EXPORT = qw(to_json from_json);	88	our @EXPORT = qw(to_json from_json);
68	require Exporter;	89	require Exporter;
69		90
70	require XSLoader;	91	require XSLoader;
71	XSLoader::load JSON::XS::, $VERSION;	92	XSLoader::load JSON::XS::, $VERSION;
72	}	93	}
…		…
76	The following convinience methods are provided by this module. They are	97	The following convinience methods are provided by this module. They are
77	exported by default:	98	exported by default:
78		99
79	=over 4	100	=over 4
80		101
81	=item $json_string = to_json $perl_scalar	102	=item $json_text = to_json $perl_scalar
82		103
83	Converts the given Perl data structure (a simple scalar or a reference to	104	Converts the given Perl data structure (a simple scalar or a reference to
84	a hash or array) to a UTF-8 encoded, binary string (that is, the string contains	105	a hash or array) to a UTF-8 encoded, binary string (that is, the string contains
85	octets only). Croaks on error.	106	octets only). Croaks on error.
86		107
87	This function call is functionally identical to C<< JSON::XS->new->utf8	108	This function call is functionally identical to:
88	(1)->encode ($perl_scalar) >>.
89		109
		110	$json_text = JSON::XS->new->utf8->encode ($perl_scalar)
		111
		112	except being faster.
		113
90	=item $perl_scalar = from_json $json_string	114	=item $perl_scalar = from_json $json_text
91		115
92	The opposite of C<to_json>: expects an UTF-8 (binary) string and tries to	116	The opposite of C<to_json>: expects an UTF-8 (binary) string and tries to
93	parse that as an UTF-8 encoded JSON string, returning the resulting simple	117	parse that as an UTF-8 encoded JSON text, returning the resulting simple
94	scalar or reference. Croaks on error.	118	scalar or reference. Croaks on error.
95		119
96	This function call is functionally identical to C<< JSON::XS->new->utf8	120	This function call is functionally identical to:
97	(1)->decode ($json_string) >>.	121
		122	$perl_scalar = JSON::XS->new->utf8->decode ($json_text)
		123
		124	except being faster.
98		125
99	=back	126	=back
100		127
101	=head1 OBJECT-ORIENTED INTERFACE	128	=head1 OBJECT-ORIENTED INTERFACE
102		129
…		…
111	strings. All boolean flags described below are by default I<disabled>.	138	strings. All boolean flags described below are by default I<disabled>.
112		139
113	The mutators for flags all return the JSON object again and thus calls can	140	The mutators for flags all return the JSON object again and thus calls can
114	be chained:	141	be chained:
115		142
116	my $json = JSON::XS->new->utf8(1)->space_after(1)->encode ({a => [1,2]})	143	my $json = JSON::XS->new->utf8->space_after->encode ({a => [1,2]})
117	=> {"a": [1, 2]}	144	=> {"a": [1, 2]}
118		145
119	=item $json = $json->ascii ([$enable])	146	=item $json = $json->ascii ([$enable])
120		147
121	If C<$enable> is true (or missing), then the C<encode> method will	148	If C<$enable> is true (or missing), then the C<encode> method will not
122	not generate characters outside the code range C<0..127>. Any unicode	149	generate characters outside the code range C<0..127> (which is ASCII). Any
123	characters outside that range will be escaped using either a single	150	unicode characters outside that range will be escaped using either a
124	\uXXXX (BMP characters) or a double \uHHHH\uLLLLL escape sequence, as per	151	single \uXXXX (BMP characters) or a double \uHHHH\uLLLLL escape sequence,
125	RFC4627.	152	as per RFC4627.
126		153
127	If C<$enable> is false, then the C<encode> method will not escape Unicode	154	If C<$enable> is false, then the C<encode> method will not escape Unicode
128	characters unless necessary.	155	characters unless required by the JSON syntax. This results in a faster
		156	and more compact format.
129		157
130	JSON::XS->new->ascii (1)->encode (chr 0x10401)	158	JSON::XS->new->ascii (1)->encode ([chr 0x10401])
131	=> \ud801\udc01	159	=> ["\ud801\udc01"]
132		160
133	=item $json = $json->utf8 ([$enable])	161	=item $json = $json->utf8 ([$enable])
134		162
135	If C<$enable> is true (or missing), then the C<encode> method will encode	163	If C<$enable> is true (or missing), then the C<encode> method will encode
136	the JSON string into UTF-8, as required by many protocols, while the	164	the JSON result into UTF-8, as required by many protocols, while the
137	C<decode> method expects to be handled an UTF-8-encoded string. Please	165	C<decode> method expects to be handled an UTF-8-encoded string. Please
138	note that UTF-8-encoded strings do not contain any characters outside the	166	note that UTF-8-encoded strings do not contain any characters outside the
139	range C<0..255>, they are thus useful for bytewise/binary I/O.	167	range C<0..255>, they are thus useful for bytewise/binary I/O. In future
		168	versions, enabling this option might enable autodetection of the UTF-16
		169	and UTF-32 encoding families, as described in RFC4627.
140		170
141	If C<$enable> is false, then the C<encode> method will return the JSON	171	If C<$enable> is false, then the C<encode> method will return the JSON
142	string as a (non-encoded) unicode string, while C<decode> expects thus a	172	string as a (non-encoded) unicode string, while C<decode> expects thus a
143	unicode string. Any decoding or encoding (e.g. to UTF-8 or UTF-16) needs	173	unicode string. Any decoding or encoding (e.g. to UTF-8 or UTF-16) needs
144	to be done yourself, e.g. using the Encode module.	174	to be done yourself, e.g. using the Encode module.
145		175
		176	Example, output UTF-16BE-encoded JSON:
		177
		178	use Encode;
		179	$jsontext = encode "UTF-16BE", JSON::XS->new->encode ($object);
		180
		181	Example, decode UTF-32LE-encoded JSON:
		182
		183	use Encode;
		184	$object = JSON::XS->new->decode (decode "UTF-32LE", $jsontext);
		185
146	=item $json = $json->pretty ([$enable])	186	=item $json = $json->pretty ([$enable])
147		187
148	This enables (or disables) all of the C<indent>, C<space_before> and	188	This enables (or disables) all of the C<indent>, C<space_before> and
149	C<space_after> (and in the future possibly more) flags in one call to	189	C<space_after> (and in the future possibly more) flags in one call to
150	generate the most readable (or most compact) form possible.	190	generate the most readable (or most compact) form possible.
		191
		192	Example, pretty-print some simple structure:
151		193
152	my $json = JSON::XS->new->pretty(1)->encode ({a => [1,2]})	194	my $json = JSON::XS->new->pretty(1)->encode ({a => [1,2]})
153	=>	195	=>
154	{	196	{
155	"a" : [	197	"a" : [
…		…
163	If C<$enable> is true (or missing), then the C<encode> method will use a multiline	205	If C<$enable> is true (or missing), then the C<encode> method will use a multiline
164	format as output, putting every array member or object/hash key-value pair	206	format as output, putting every array member or object/hash key-value pair
165	into its own line, identing them properly.	207	into its own line, identing them properly.
166		208
167	If C<$enable> is false, no newlines or indenting will be produced, and the	209	If C<$enable> is false, no newlines or indenting will be produced, and the
168	resulting JSON strings is guarenteed not to contain any C<newlines>.	210	resulting JSON text is guarenteed not to contain any C<newlines>.
169		211
170	This setting has no effect when decoding JSON strings.	212	This setting has no effect when decoding JSON texts.
171		213
172	=item $json = $json->space_before ([$enable])	214	=item $json = $json->space_before ([$enable])
173		215
174	If C<$enable> is true (or missing), then the C<encode> method will add an extra	216	If C<$enable> is true (or missing), then the C<encode> method will add an extra
175	optional space before the C<:> separating keys from values in JSON objects.	217	optional space before the C<:> separating keys from values in JSON objects.
176		218
177	If C<$enable> is false, then the C<encode> method will not add any extra	219	If C<$enable> is false, then the C<encode> method will not add any extra
178	space at those places.	220	space at those places.
179		221
180	This setting has no effect when decoding JSON strings. You will also most	222	This setting has no effect when decoding JSON texts. You will also
181	likely combine this setting with C<space_after>.	223	most likely combine this setting with C<space_after>.
		224
		225	Example, space_before enabled, space_after and indent disabled:
		226
		227	{"key" :"value"}
182		228
183	=item $json = $json->space_after ([$enable])	229	=item $json = $json->space_after ([$enable])
184		230
185	If C<$enable> is true (or missing), then the C<encode> method will add an extra	231	If C<$enable> is true (or missing), then the C<encode> method will add an extra
186	optional space after the C<:> separating keys from values in JSON objects	232	optional space after the C<:> separating keys from values in JSON objects
…		…
188	members.	234	members.
189		235
190	If C<$enable> is false, then the C<encode> method will not add any extra	236	If C<$enable> is false, then the C<encode> method will not add any extra
191	space at those places.	237	space at those places.
192		238
193	This setting has no effect when decoding JSON strings.	239	This setting has no effect when decoding JSON texts.
		240
		241	Example, space_before and indent disabled, space_after enabled:
		242
		243	{"key": "value"}
194		244
195	=item $json = $json->canonical ([$enable])	245	=item $json = $json->canonical ([$enable])
196		246
197	If C<$enable> is true (or missing), then the C<encode> method will output JSON objects	247	If C<$enable> is true (or missing), then the C<encode> method will output JSON objects
198	by sorting their keys. This is adding a comparatively high overhead.	248	by sorting their keys. This is adding a comparatively high overhead.
…		…
200	If C<$enable> is false, then the C<encode> method will output key-value	250	If C<$enable> is false, then the C<encode> method will output key-value
201	pairs in the order Perl stores them (which will likely change between runs	251	pairs in the order Perl stores them (which will likely change between runs
202	of the same script).	252	of the same script).
203		253
204	This option is useful if you want the same data structure to be encoded as	254	This option is useful if you want the same data structure to be encoded as
205	the same JSON string (given the same overall settings). If it is disabled,	255	the same JSON text (given the same overall settings). If it is disabled,
206	the same hash migh be encoded differently even if contains the same data,	256	the same hash migh be encoded differently even if contains the same data,
207	as key-value pairs have no inherent ordering in Perl.	257	as key-value pairs have no inherent ordering in Perl.
208		258
209	This setting has no effect when decoding JSON strings.	259	This setting has no effect when decoding JSON texts.
210		260
211	=item $json = $json->allow_nonref ([$enable])	261	=item $json = $json->allow_nonref ([$enable])
212		262
213	If C<$enable> is true (or missing), then the C<encode> method can convert a	263	If C<$enable> is true (or missing), then the C<encode> method can convert a
214	non-reference into its corresponding string, number or null JSON value,	264	non-reference into its corresponding string, number or null JSON value,
215	which is an extension to RFC4627. Likewise, C<decode> will accept those JSON	265	which is an extension to RFC4627. Likewise, C<decode> will accept those JSON
216	values instead of croaking.	266	values instead of croaking.
217		267
218	If C<$enable> is false, then the C<encode> method will croak if it isn't	268	If C<$enable> is false, then the C<encode> method will croak if it isn't
219	passed an arrayref or hashref, as JSON strings must either be an object	269	passed an arrayref or hashref, as JSON texts must either be an object
220	or array. Likewise, C<decode> will croak if given something that is not a	270	or array. Likewise, C<decode> will croak if given something that is not a
221	JSON object or array.	271	JSON object or array.
		272
		273	Example, encode a Perl scalar as JSON value with enabled C<allow_nonref>,
		274	resulting in an invalid JSON text:
		275
		276	JSON::XS->new->allow_nonref->encode ("Hello, World!")
		277	=> "Hello, World!"
222		278
223	=item $json = $json->shrink ([$enable])	279	=item $json = $json->shrink ([$enable])
224		280
225	Perl usually over-allocates memory a bit when allocating space for	281	Perl usually over-allocates memory a bit when allocating space for
226	strings. This flag optionally resizes strings generated by either	282	strings. This flag optionally resizes strings generated by either
227	C<encode> or C<decode> to their minimum size possible. This can save	283	C<encode> or C<decode> to their minimum size possible. This can save
228	memory when your JSON strings are either very very long or you have many	284	memory when your JSON texts are either very very long or you have many
229	short strings. It will also try to downgrade any strings to octet-form	285	short strings. It will also try to downgrade any strings to octet-form
230	if possible: perl stores strings internally either in an encoding called	286	if possible: perl stores strings internally either in an encoding called
231	UTF-X or in octet-form. The latter cannot store everything but uses less	287	UTF-X or in octet-form. The latter cannot store everything but uses less
232	space in general.	288	space in general.
233		289
…		…
239		295
240	In the future, this setting might control other things, such as converting	296	In the future, this setting might control other things, such as converting
241	strings that look like integers or floats into integers or floats	297	strings that look like integers or floats into integers or floats
242	internally (there is no difference on the Perl level), saving space.	298	internally (there is no difference on the Perl level), saving space.
243		299
244	=item $json_string = $json->encode ($perl_scalar)	300	=item $json_text = $json->encode ($perl_scalar)
245		301
246	Converts the given Perl data structure (a simple scalar or a reference	302	Converts the given Perl data structure (a simple scalar or a reference
247	to a hash or array) to its JSON representation. Simple scalars will be	303	to a hash or array) to its JSON representation. Simple scalars will be
248	converted into JSON string or number sequences, while references to arrays	304	converted into JSON string or number sequences, while references to arrays
249	become JSON arrays and references to hashes become JSON objects. Undefined	305	become JSON arrays and references to hashes become JSON objects. Undefined
250	Perl values (e.g. C<undef>) become JSON C<null> values. Neither C<true>	306	Perl values (e.g. C<undef>) become JSON C<null> values. Neither C<true>
251	nor C<false> values will be generated.	307	nor C<false> values will be generated.
252		308
253	=item $perl_scalar = $json->decode ($json_string)	309	=item $perl_scalar = $json->decode ($json_text)
254		310
255	The opposite of C<encode>: expects a JSON string and tries to parse it,	311	The opposite of C<encode>: expects a JSON text and tries to parse it,
256	returning the resulting simple scalar or reference. Croaks on error.	312	returning the resulting simple scalar or reference. Croaks on error.
257		313
258	JSON numbers and strings become simple Perl scalars. JSON arrays become	314	JSON numbers and strings become simple Perl scalars. JSON arrays become
259	Perl arrayrefs and JSON objects become Perl hashrefs. C<true> becomes	315	Perl arrayrefs and JSON objects become Perl hashrefs. C<true> becomes
260	C<1>, C<false> becomes C<0> and C<null> becomes C<undef>.	316	C<1>, C<false> becomes C<0> and C<null> becomes C<undef>.
		317
		318	=back
		319
		320	=head1 MAPPING
		321
		322	This section describes how JSON::XS maps Perl values to JSON values and
		323	vice versa. These mappings are designed to "do the right thing" in most
		324	circumstances automatically, preserving round-tripping characteristics
		325	(what you put in comes out as something equivalent).
		326
		327	For the more enlightened: note that in the following descriptions,
		328	lowercase I<perl> refers to the Perl interpreter, while uppcercase I<Perl>
		329	refers to the abstract Perl language itself.
		330
		331	=head2 JSON -> PERL
		332
		333	=over 4
		334
		335	=item object
		336
		337	A JSON object becomes a reference to a hash in Perl. No ordering of object
		338	keys is preserved (JSON does not preserver object key ordering itself).
		339
		340	=item array
		341
		342	A JSON array becomes a reference to an array in Perl.
		343
		344	=item string
		345
		346	A JSON string becomes a string scalar in Perl - Unicode codepoints in JSON
		347	are represented by the same codepoints in the Perl string, so no manual
		348	decoding is necessary.
		349
		350	=item number
		351
		352	A JSON number becomes either an integer or numeric (floating point)
		353	scalar in perl, depending on its range and any fractional parts. On the
		354	Perl level, there is no difference between those as Perl handles all the
		355	conversion details, but an integer may take slightly less memory and might
		356	represent more values exactly than (floating point) numbers.
		357
		358	=item true, false
		359
		360	These JSON atoms become C<0>, C<1>, respectively. Information is lost in
		361	this process. Future versions might represent those values differently,
		362	but they will be guarenteed to act like these integers would normally in
		363	Perl.
		364
		365	=item null
		366
		367	A JSON null atom becomes C<undef> in Perl.
		368
		369	=back
		370
		371	=head2 PERL -> JSON
		372
		373	The mapping from Perl to JSON is slightly more difficult, as Perl is a
		374	truly typeless language, so we can only guess which JSON type is meant by
		375	a Perl value.
		376
		377	=over 4
		378
		379	=item hash references
		380
		381	Perl hash references become JSON objects. As there is no inherent ordering
		382	in hash keys, they will usually be encoded in a pseudo-random order that
		383	can change between runs of the same program but stays generally the same
		384	within a single run of a program. JSON::XS can optionally sort the hash
		385	keys (determined by the I<canonical> flag), so the same datastructure
		386	will serialise to the same JSON text (given same settings and version of
		387	JSON::XS), but this incurs a runtime overhead.
		388
		389	=item array references
		390
		391	Perl array references become JSON arrays.
		392
		393	=item blessed objects
		394
		395	Blessed objects are not allowed. JSON::XS currently tries to encode their
		396	underlying representation (hash- or arrayref), but this behaviour might
		397	change in future versions.
		398
		399	=item simple scalars
		400
		401	Simple Perl scalars (any scalar that is not a reference) are the most
		402	difficult objects to encode: JSON::XS will encode undefined scalars as
		403	JSON null value, scalars that have last been used in a string context
		404	before encoding as JSON strings and anything else as number value:
		405
		406	# dump as number
		407	to_json [2] # yields [2]
		408	to_json [-3.0e17] # yields [-3e+17]
		409	my $value = 5; to_json [$value] # yields [5]
		410
		411	# used as string, so dump as string
		412	print $value;
		413	to_json [$value] # yields ["5"]
		414
		415	# undef becomes null
		416	to_json [undef] # yields [null]
		417
		418	You can force the type to be a string by stringifying it:
		419
		420	my $x = 3.1; # some variable containing a number
		421	"$x"; # stringified
		422	$x .= ""; # another, more awkward way to stringify
		423	print $x; # perl does it for you, too, quite often
		424
		425	You can force the type to be a number by numifying it:
		426
		427	my $x = "3"; # some variable containing a string
		428	$x += 0; # numify it, ensuring it will be dumped as a number
		429	$x *= 1; # same thing, the choise is yours.
		430
		431	You can not currently output JSON booleans or force the type in other,
		432	less obscure, ways. Tell me if you need this capability.
		433
		434	=item circular data structures
		435
		436	Those will be encoded until memory or stackspace runs out.
261		437
262	=back	438	=back
263		439
264	=head1 COMPARISON	440	=head1 COMPARISON
265		441
…		…
293		469
294	Has problems handling many Perl values (e.g. regex results and other magic	470	Has problems handling many Perl values (e.g. regex results and other magic
295	values will make it croak).	471	values will make it croak).
296		472
297	Does not even generate valid JSON (C<{1,2}> gets converted to C<{1:2}>	473	Does not even generate valid JSON (C<{1,2}> gets converted to C<{1:2}>
298	which is not a valid JSON string.	474	which is not a valid JSON text.
299		475
300	Unmaintained (maintainer unresponsive for many months, bugs are not	476	Unmaintained (maintainer unresponsive for many months, bugs are not
301	getting fixed).	477	getting fixed).
302		478
303	=item JSON::Syck 0.21	479	=item JSON::Syck 0.21
…		…
305	Very buggy (often crashes).	481	Very buggy (often crashes).
306		482
307	Very inflexible (no human-readable format supported, format pretty much	483	Very inflexible (no human-readable format supported, format pretty much
308	undocumented. I need at least a format for easy reading by humans and a	484	undocumented. I need at least a format for easy reading by humans and a
309	single-line compact format for use in a protocol, and preferably a way to	485	single-line compact format for use in a protocol, and preferably a way to
310	generate ASCII-only JSON strings).	486	generate ASCII-only JSON texts).
311		487
312	Completely broken (and confusingly documented) Unicode handling (unicode	488	Completely broken (and confusingly documented) Unicode handling (unicode
313	escapes are not working properly, you need to set ImplicitUnicode to	489	escapes are not working properly, you need to set ImplicitUnicode to
314	I<different> values on en- and decoding to get symmetric behaviour).	490	I<different> values on en- and decoding to get symmetric behaviour).
315		491
…		…
338		514
339	Very inflexible.	515	Very inflexible.
340		516
341	No roundtripping.	517	No roundtripping.
342		518
343	Does not generate valid JSON (key strings are often unquoted, empty keys	519	Does not generate valid JSON texts (key strings are often unquoted, empty keys
344	result in nothing being output)	520	result in nothing being output)
345		521
346	Does not check input for validity.	522	Does not check input for validity.
347		523
348	=back	524	=back
…		…
352	It seems that JSON::XS is surprisingly fast, as shown in the following	528	It seems that JSON::XS is surprisingly fast, as shown in the following
353	tables. They have been generated with the help of the C<eg/bench> program	529	tables. They have been generated with the help of the C<eg/bench> program
354	in the JSON::XS distribution, to make it easy to compare on your own	530	in the JSON::XS distribution, to make it easy to compare on your own
355	system.	531	system.
356		532
357	First is a comparison between various modules using a very simple JSON	533	First comes a comparison between various modules using a very short JSON
		534	string:
		535
		536	{"method": "handleMessage", "params": ["user1", "we were just talking"], "id": null}
		537
358	string, showing the number of encodes/decodes per second (JSON::XS is	538	It shows the number of encodes/decodes per second (JSON::XS uses the
359	the functional interface, while JSON::XS/2 is the OO interface with	539	functional interface, while JSON::XS/2 uses the OO interface with
360	pretty-printing and hashkey sorting enabled).	540	pretty-printing and hashkey sorting enabled). Higher is better:
361		541
362	module \| encode \| decode \|	542	module \| encode \| decode \|
363	-----------\|------------\|------------\|	543	-----------\|------------\|------------\|
364	JSON \| 14006 \| 6820 \|	544	JSON \| 11488.516 \| 7823.035 \|
365	JSON::DWIW \| 200937 \| 120386 \|	545	JSON::DWIW \| 94708.054 \| 129094.260 \|
366	JSON::PC \| 85065 \| 129366 \|	546	JSON::PC \| 63884.157 \| 128528.212 \|
367	JSON::Syck \| 59898 \| 44232 \|	547	JSON::Syck \| 34898.677 \| 42096.911 \|
368	JSON::XS \| 1171478 \| 342435 \|	548	JSON::XS \| 654027.064 \| 396423.669 \|
369	JSON::XS/2 \| 730760 \| 328714 \|	549	JSON::XS/2 \| 371564.190 \| 371725.613 \|
370	-----------+------------+------------+	550	-----------+------------+------------+
371		551
372	That is, JSON::XS is 6 times faster than than JSON::DWIW and about 80	552	That is, JSON::XS is more than six times faster than JSON::DWIW on
		553	encoding, more than three times faster on decoding, and about thirty times
373	times faster than JSON, even with pretty-printing and key sorting.	554	faster than JSON, even with pretty-printing and key sorting.
374		555
375	Using a longer test string (roughly 8KB, generated from Yahoo! Locals	556	Using a longer test string (roughly 18KB, generated from Yahoo! Locals
376	search API (http://nanoref.com/yahooapis/mgPdGg):	557	search API (http://nanoref.com/yahooapis/mgPdGg):
377		558
378	module \| encode \| decode \|	559	module \| encode \| decode \|
379	-----------\|------------\|------------\|	560	-----------\|------------\|------------\|
380	JSON \| 673 \| 38 \|	561	JSON \| 273.023 \| 44.674 \|
381	JSON::DWIW \| 5271 \| 770 \|	562	JSON::DWIW \| 1089.383 \| 1145.704 \|
382	JSON::PC \| 9901 \| 2491 \|	563	JSON::PC \| 3097.419 \| 2393.921 \|
383	JSON::Syck \| 2360 \| 786 \|	564	JSON::Syck \| 514.060 \| 843.053 \|
384	JSON::XS \| 37398 \| 3202 \|	565	JSON::XS \| 6479.668 \| 3636.364 \|
385	JSON::XS/2 \| 13765 \| 3153 \|	566	JSON::XS/2 \| 3774.221 \| 3599.124 \|
386	-----------+------------+------------+	567	-----------+------------+------------+
387		568
388	Again, JSON::XS leads by far in the encoding case, while still beating	569	Again, JSON::XS leads by far.
389	every other module in the decoding case.
390		570
391	Last example is an almost 8MB large hash with many large binary values	571	On large strings containing lots of high unicode characters, some modules
392	(PNG files), resulting in a lot of escaping:	572	(such as JSON::PC) seem to decode faster than JSON::XS, but the result
		573	will be broken due to missing (or wrong) unicode handling. Others refuse
		574	to decode or encode properly, so it was impossible to prepare a fair
		575	comparison table for that case.
		576
		577	=head1 RESOURCE LIMITS
		578
		579	JSON::XS does not impose any limits on the size of JSON texts or Perl
		580	values they represent - if your machine can handle it, JSON::XS will
		581	encode or decode it. Future versions might optionally impose structure
		582	depth and memory use resource limits.
393		583
394	=head1 BUGS	584	=head1 BUGS
395		585
396	While the goal of this module is to be correct, that unfortunately does	586	While the goal of this module is to be correct, that unfortunately does
397	not mean its bug-free, only that I think its design is bug-free. It is	587	not mean its bug-free, only that I think its design is bug-free. It is

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Comparing JSON-XS/XS.pm (file contents): Revision 1.9 by root, Fri Mar 23 16:00:19 2007 UTC vs. Revision 1.20 by root, Sun Mar 25 00:47:42 2007 UTC

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Comparing JSON-XS/XS.pm (file contents):
Revision 1.9 by root, Fri Mar 23 16:00:19 2007 UTC vs.
Revision 1.20 by root, Sun Mar 25 00:47:42 2007 UTC