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

Comparing JSON-XS/XS.pm (file contents):
Revision 1.31 by root, Wed Apr 11 12:23:02 2007 UTC vs.
Revision 1.59 by root, Mon Aug 27 01:49:01 2007 UTC

…		…
9	# exported functions, they croak on error	9	# exported functions, they croak on error
10	# and expect/generate UTF-8	10	# and expect/generate UTF-8
11		11
12	$utf8_encoded_json_text = to_json $perl_hash_or_arrayref;	12	$utf8_encoded_json_text = to_json $perl_hash_or_arrayref;
13	$perl_hash_or_arrayref = from_json $utf8_encoded_json_text;	13	$perl_hash_or_arrayref = from_json $utf8_encoded_json_text;
14
15	# objToJson and jsonToObj aliases to to_json and from_json
16	# are exported for compatibility to the JSON module,
17	# but should not be used in new code.
18		14
19	# OO-interface	15	# OO-interface
20		16
21	$coder = JSON::XS->new->ascii->pretty->allow_nonref;	17	$coder = JSON::XS->new->ascii->pretty->allow_nonref;
22	$pretty_printed_unencoded = $coder->encode ($perl_scalar);	18	$pretty_printed_unencoded = $coder->encode ($perl_scalar);
…		…
85		81
86	package JSON::XS;	82	package JSON::XS;
87		83
88	use strict;	84	use strict;
89		85
90	BEGIN {
91	our $VERSION = '1.12';	86	our $VERSION = '1.5';
92	our @ISA = qw(Exporter);	87	our @ISA = qw(Exporter);
93		88
94	our @EXPORT = qw(to_json from_json objToJson jsonToObj);	89	our @EXPORT = qw(to_json from_json);
95	require Exporter;
96		90
97	require XSLoader;	91	use Exporter;
98	XSLoader::load JSON::XS::, $VERSION;	92	use XSLoader;
99	}
100		93
101	=head1 FUNCTIONAL INTERFACE	94	=head1 FUNCTIONAL INTERFACE
102		95
103	The following convinience methods are provided by this module. They are	96	The following convinience methods are provided by this module. They are
104	exported by default:	97	exported by default:
…		…
126	This function call is functionally identical to:	119	This function call is functionally identical to:
127		120
128	$perl_scalar = JSON::XS->new->utf8->decode ($json_text)	121	$perl_scalar = JSON::XS->new->utf8->decode ($json_text)
129		122
130	except being faster.	123	except being faster.
		124
		125	=item $is_boolean = JSON::XS::is_bool $scalar
		126
		127	Returns true if the passed scalar represents either JSON::XS::true or
		128	JSON::XS::false, two constants that act like C<1> and C<0>, respectively
		129	and are used to represent JSON C<true> and C<false> values in Perl.
		130
		131	See MAPPING, below, for more information on how JSON values are mapped to
		132	Perl.
131		133
132	=back	134	=back
133		135
134		136
135	=head1 OBJECT-ORIENTED INTERFACE	137	=head1 OBJECT-ORIENTED INTERFACE
…		…
154		156
155	If C<$enable> is true (or missing), then the C<encode> method will not	157	If C<$enable> is true (or missing), then the C<encode> method will not
156	generate characters outside the code range C<0..127> (which is ASCII). Any	158	generate characters outside the code range C<0..127> (which is ASCII). Any
157	unicode characters outside that range will be escaped using either a	159	unicode characters outside that range will be escaped using either a
158	single \uXXXX (BMP characters) or a double \uHHHH\uLLLLL escape sequence,	160	single \uXXXX (BMP characters) or a double \uHHHH\uLLLLL escape sequence,
159	as per RFC4627.	161	as per RFC4627. The resulting encoded JSON text can be treated as a native
		162	unicode string, an ascii-encoded, latin1-encoded or UTF-8 encoded string,
		163	or any other superset of ASCII.
160		164
161	If C<$enable> is false, then the C<encode> method will not escape Unicode	165	If C<$enable> is false, then the C<encode> method will not escape Unicode
162	characters unless required by the JSON syntax. This results in a faster	166	characters unless required by the JSON syntax or other flags. This results
163	and more compact format.	167	in a faster and more compact format.
		168
		169	The main use for this flag is to produce JSON texts that can be
		170	transmitted over a 7-bit channel, as the encoded JSON texts will not
		171	contain any 8 bit characters.
164		172
165	JSON::XS->new->ascii (1)->encode ([chr 0x10401])	173	JSON::XS->new->ascii (1)->encode ([chr 0x10401])
166	=> ["\ud801\udc01"]	174	=> ["\ud801\udc01"]
		175
		176	=item $json = $json->latin1 ([$enable])
		177
		178	If C<$enable> is true (or missing), then the C<encode> method will encode
		179	the resulting JSON text as latin1 (or iso-8859-1), escaping any characters
		180	outside the code range C<0..255>. The resulting string can be treated as a
		181	latin1-encoded JSON text or a native unicode string. The C<decode> method
		182	will not be affected in any way by this flag, as C<decode> by default
		183	expects unicode, which is a strict superset of latin1.
		184
		185	If C<$enable> is false, then the C<encode> method will not escape Unicode
		186	characters unless required by the JSON syntax or other flags.
		187
		188	The main use for this flag is efficiently encoding binary data as JSON
		189	text, as most octets will not be escaped, resulting in a smaller encoded
		190	size. The disadvantage is that the resulting JSON text is encoded
		191	in latin1 (and must correctly be treated as such when storing and
		192	transfering), a rare encoding for JSON. It is therefore most useful when
		193	you want to store data structures known to contain binary data efficiently
		194	in files or databases, not when talking to other JSON encoders/decoders.
		195
		196	JSON::XS->new->latin1->encode (["\x{89}\x{abc}"]
		197	=> ["\x{89}\\u0abc"] # (perl syntax, U+abc escaped, U+89 not)
167		198
168	=item $json = $json->utf8 ([$enable])	199	=item $json = $json->utf8 ([$enable])
169		200
170	If C<$enable> is true (or missing), then the C<encode> method will encode	201	If C<$enable> is true (or missing), then the C<encode> method will encode
171	the JSON result into UTF-8, as required by many protocols, while the	202	the JSON result into UTF-8, as required by many protocols, while the
…		…
247		278
248	Example, space_before and indent disabled, space_after enabled:	279	Example, space_before and indent disabled, space_after enabled:
249		280
250	{"key": "value"}	281	{"key": "value"}
251		282
		283	=item $json = $json->relaxed ([$enable])
		284
		285	If C<$enable> is true (or missing), then C<decode> will accept some
		286	extensions to normal JSON syntax (see below). C<encode> will not be
		287	affected in anyway. I<Be aware that this option makes you accept invalid
		288	JSON texts as if they were valid!>. I suggest only to use this option to
		289	parse application-specific files written by humans (configuration files,
		290	resource files etc.)
		291
		292	If C<$enable> is false (the default), then C<decode> will only accept
		293	valid JSON texts.
		294
		295	Currently accepted extensions are:
		296
		297	=over 4
		298
		299	=item * list items can have an end-comma
		300
		301	JSON I<separates> array elements and key-value pairs with commas. This
		302	can be annoying if you write JSON texts manually and want to be able to
		303	quickly append elements, so this extension accepts comma at the end of
		304	such items not just between them:
		305
		306	[
		307	1,
		308	2, <- this comma not normally allowed
		309	]
		310	{
		311	"k1": "v1",
		312	"k2": "v2", <- this comma not normally allowed
		313	}
		314
		315	=back
		316
252	=item $json = $json->canonical ([$enable])	317	=item $json = $json->canonical ([$enable])
253		318
254	If C<$enable> is true (or missing), then the C<encode> method will output JSON objects	319	If C<$enable> is true (or missing), then the C<encode> method will output JSON objects
255	by sorting their keys. This is adding a comparatively high overhead.	320	by sorting their keys. This is adding a comparatively high overhead.
256		321
…		…
280	Example, encode a Perl scalar as JSON value with enabled C<allow_nonref>,	345	Example, encode a Perl scalar as JSON value with enabled C<allow_nonref>,
281	resulting in an invalid JSON text:	346	resulting in an invalid JSON text:
282		347
283	JSON::XS->new->allow_nonref->encode ("Hello, World!")	348	JSON::XS->new->allow_nonref->encode ("Hello, World!")
284	=> "Hello, World!"	349	=> "Hello, World!"
		350
		351	=item $json = $json->allow_blessed ([$enable])
		352
		353	If C<$enable> is true (or missing), then the C<encode> method will not
		354	barf when it encounters a blessed reference. Instead, the value of the
		355	B<convert_blessed> option will decide wether C<null> (C<convert_blessed>
		356	disabled or no C<to_json> method found) or a representation of the
		357	object (C<convert_blessed> enabled and C<to_json> method found) is being
		358	encoded. Has no effect on C<decode>.
		359
		360	If C<$enable> is false (the default), then C<encode> will throw an
		361	exception when it encounters a blessed object.
		362
		363	=item $json = $json->convert_blessed ([$enable])
		364
		365	If C<$enable> is true (or missing), then C<encode>, upon encountering a
		366	blessed object, will check for the availability of the C<TO_JSON> method
		367	on the object's class. If found, it will be called in scalar context
		368	and the resulting scalar will be encoded instead of the object. If no
		369	C<TO_JSON> method is found, the value of C<allow_blessed> will decide what
		370	to do.
		371
		372	The C<TO_JSON> method may safely call die if it wants. If C<TO_JSON>
		373	returns other blessed objects, those will be handled in the same
		374	way. C<TO_JSON> must take care of not causing an endless recursion cycle
		375	(== crash) in this case. The name of C<TO_JSON> was chosen because other
		376	methods called by the Perl core (== not by the user of the object) are
		377	usually in upper case letters and to avoid collisions with the C<to_json>
		378	function.
		379
		380	This setting does not yet influence C<decode> in any way, but in the
		381	future, global hooks might get installed that influence C<decode> and are
		382	enabled by this setting.
		383
		384	If C<$enable> is false, then the C<allow_blessed> setting will decide what
		385	to do when a blessed object is found.
		386
		387	=item $json = $json->filter_json_object ([$coderef->($hashref)])
		388
		389	When C<$coderef> is specified, it will be called from C<decode> each
		390	time it decodes a JSON object. The only argument is a reference to the
		391	newly-created hash. If the code references returns a single scalar (which
		392	need not be a reference), this value (i.e. a copy of that scalar to avoid
		393	aliasing) is inserted into the deserialised data structure. If it returns
		394	an empty list (NOTE: I<not> C<undef>, which is a valid scalar), the
		395	original deserialised hash will be inserted. This setting can slow down
		396	decoding considerably.
		397
		398	When C<$coderef> is omitted or undefined, any existing callback will
		399	be removed and C<decode> will not change the deserialised hash in any
		400	way.
		401
		402	Example, convert all JSON objects into the integer 5:
		403
		404	my $js = JSON::XS->new->filter_json_object (sub { 5 });
		405	# returns [5]
		406	$js->decode ('[{}]')
		407	# throw an exception because allow_nonref is not enabled
		408	# so a lone 5 is not allowed.
		409	$js->decode ('{"a":1, "b":2}');
		410
		411	=item $json = $json->filter_json_single_key_object ($key [=> $coderef->($value)])
		412
		413	Works remotely similar to C<filter_json_object>, but is only called for
		414	JSON objects having a single key named C<$key>.
		415
		416	This C<$coderef> is called before the one specified via
		417	C<filter_json_object>, if any. It gets passed the single value in the JSON
		418	object. If it returns a single value, it will be inserted into the data
		419	structure. If it returns nothing (not even C<undef> but the empty list),
		420	the callback from C<filter_json_object> will be called next, as if no
		421	single-key callback were specified.
		422
		423	If C<$coderef> is omitted or undefined, the corresponding callback will be
		424	disabled. There can only ever be one callback for a given key.
		425
		426	As this callback gets called less often then the C<filter_json_object>
		427	one, decoding speed will not usually suffer as much. Therefore, single-key
		428	objects make excellent targets to serialise Perl objects into, especially
		429	as single-key JSON objects are as close to the type-tagged value concept
		430	as JSON gets (its basically an ID/VALUE tuple). Of course, JSON does not
		431	support this in any way, so you need to make sure your data never looks
		432	like a serialised Perl hash.
		433
		434	Typical names for the single object key are C<__class_whatever__>, or
		435	C<$__dollars_are_rarely_used__$> or C<}ugly_brace_placement>, or even
		436	things like C<__class_md5sum(classname)__>, to reduce the risk of clashing
		437	with real hashes.
		438
		439	Example, decode JSON objects of the form C<< { "__widget__" => <id> } >>
		440	into the corresponding C<< $WIDGET{<id>} >> object:
		441
		442	# return whatever is in $WIDGET{5}:
		443	JSON::XS
		444	->new
		445	->filter_json_single_key_object (__widget__ => sub {
		446	$WIDGET{ $_[0] }
		447	})
		448	->decode ('{"__widget__": 5')
		449
		450	# this can be used with a TO_JSON method in some "widget" class
		451	# for serialisation to json:
		452	sub WidgetBase::TO_JSON {
		453	my ($self) = @_;
		454
		455	unless ($self->{id}) {
		456	$self->{id} = ..get..some..id..;
		457	$WIDGET{$self->{id}} = $self;
		458	}
		459
		460	{ __widget__ => $self->{id} }
		461	}
285		462
286	=item $json = $json->shrink ([$enable])	463	=item $json = $json->shrink ([$enable])
287		464
288	Perl usually over-allocates memory a bit when allocating space for	465	Perl usually over-allocates memory a bit when allocating space for
289	strings. This flag optionally resizes strings generated by either	466	strings. This flag optionally resizes strings generated by either
…		…
322	given character in a string.	499	given character in a string.
323		500
324	Setting the maximum depth to one disallows any nesting, so that ensures	501	Setting the maximum depth to one disallows any nesting, so that ensures
325	that the object is only a single hash/object or array.	502	that the object is only a single hash/object or array.
326		503
327	The argument to C<max_depth> will be rounded up to the next nearest power	504	The argument to C<max_depth> will be rounded up to the next highest power
328	of two.	505	of two. If no argument is given, the highest possible setting will be
		506	used, which is rarely useful.
		507
		508	See SECURITY CONSIDERATIONS, below, for more info on why this is useful.
		509
		510	=item $json = $json->max_size ([$maximum_string_size])
		511
		512	Set the maximum length a JSON text may have (in bytes) where decoding is
		513	being attempted. The default is C<0>, meaning no limit. When C<decode>
		514	is called on a string longer then this number of characters it will not
		515	attempt to decode the string but throw an exception. This setting has no
		516	effect on C<encode> (yet).
		517
		518	The argument to C<max_size> will be rounded up to the next B<highest>
		519	power of two (so may be more than requested). If no argument is given, the
		520	limit check will be deactivated (same as when C<0> is specified).
329		521
330	See SECURITY CONSIDERATIONS, below, for more info on why this is useful.	522	See SECURITY CONSIDERATIONS, below, for more info on why this is useful.
331		523
332	=item $json_text = $json->encode ($perl_scalar)	524	=item $json_text = $json->encode ($perl_scalar)
333		525
…		…
345		537
346	JSON numbers and strings become simple Perl scalars. JSON arrays become	538	JSON numbers and strings become simple Perl scalars. JSON arrays become
347	Perl arrayrefs and JSON objects become Perl hashrefs. C<true> becomes	539	Perl arrayrefs and JSON objects become Perl hashrefs. C<true> becomes
348	C<1>, C<false> becomes C<0> and C<null> becomes C<undef>.	540	C<1>, C<false> becomes C<0> and C<null> becomes C<undef>.
349		541
		542	=item ($perl_scalar, $characters) = $json->decode_prefix ($json_text)
		543
		544	This works like the C<decode> method, but instead of raising an exception
		545	when there is trailing garbage after the first JSON object, it will
		546	silently stop parsing there and return the number of characters consumed
		547	so far.
		548
		549	This is useful if your JSON texts are not delimited by an outer protocol
		550	(which is not the brightest thing to do in the first place) and you need
		551	to know where the JSON text ends.
		552
		553	JSON::XS->new->decode_prefix ("[1] the tail")
		554	=> ([], 3)
		555
350	=back	556	=back
351		557
352		558
353	=head1 MAPPING	559	=head1 MAPPING
354		560
…		…
359		565
360	For the more enlightened: note that in the following descriptions,	566	For the more enlightened: note that in the following descriptions,
361	lowercase I<perl> refers to the Perl interpreter, while uppcercase I<Perl>	567	lowercase I<perl> refers to the Perl interpreter, while uppcercase I<Perl>
362	refers to the abstract Perl language itself.	568	refers to the abstract Perl language itself.
363		569
		570
364	=head2 JSON -> PERL	571	=head2 JSON -> PERL
365		572
366	=over 4	573	=over 4
367		574
368	=item object	575	=item object
…		…
380	are represented by the same codepoints in the Perl string, so no manual	587	are represented by the same codepoints in the Perl string, so no manual
381	decoding is necessary.	588	decoding is necessary.
382		589
383	=item number	590	=item number
384		591
385	A JSON number becomes either an integer or numeric (floating point)	592	A JSON number becomes either an integer, numeric (floating point) or
386	scalar in perl, depending on its range and any fractional parts. On the	593	string scalar in perl, depending on its range and any fractional parts. On
387	Perl level, there is no difference between those as Perl handles all the	594	the Perl level, there is no difference between those as Perl handles all
388	conversion details, but an integer may take slightly less memory and might	595	the conversion details, but an integer may take slightly less memory and
389	represent more values exactly than (floating point) numbers.	596	might represent more values exactly than (floating point) numbers.
		597
		598	If the number consists of digits only, JSON::XS will try to represent
		599	it as an integer value. If that fails, it will try to represent it as
		600	a numeric (floating point) value if that is possible without loss of
		601	precision. Otherwise it will preserve the number as a string value.
		602
		603	Numbers containing a fractional or exponential part will always be
		604	represented as numeric (floating point) values, possibly at a loss of
		605	precision.
		606
		607	This might create round-tripping problems as numbers might become strings,
		608	but as Perl is typeless there is no other way to do it.
390		609
391	=item true, false	610	=item true, false
392		611
393	These JSON atoms become C<0>, C<1>, respectively. Information is lost in	612	These JSON atoms become C<JSON::XS::true> and C<JSON::XS::false>,
394	this process. Future versions might represent those values differently,	613	respectively. They are overloaded to act almost exactly like the numbers
395	but they will be guarenteed to act like these integers would normally in	614	C<1> and C<0>. You can check wether a scalar is a JSON boolean by using
396	Perl.	615	the C<JSON::XS::is_bool> function.
397		616
398	=item null	617	=item null
399		618
400	A JSON null atom becomes C<undef> in Perl.	619	A JSON null atom becomes C<undef> in Perl.
401		620
402	=back	621	=back
		622
403		623
404	=head2 PERL -> JSON	624	=head2 PERL -> JSON
405		625
406	The mapping from Perl to JSON is slightly more difficult, as Perl is a	626	The mapping from Perl to JSON is slightly more difficult, as Perl is a
407	truly typeless language, so we can only guess which JSON type is meant by	627	truly typeless language, so we can only guess which JSON type is meant by
…		…
432	C<1>, which get turned into C<false> and C<true> atoms in JSON. You can	652	C<1>, which get turned into C<false> and C<true> atoms in JSON. You can
433	also use C<JSON::XS::false> and C<JSON::XS::true> to improve readability.	653	also use C<JSON::XS::false> and C<JSON::XS::true> to improve readability.
434		654
435	to_json [\0,JSON::XS::true] # yields [false,true]	655	to_json [\0,JSON::XS::true] # yields [false,true]
436		656
		657	=item JSON::XS::true, JSON::XS::false
		658
		659	These special values become JSON true and JSON false values,
		660	respectively. You cna alos use C<\1> and C<\0> directly if you want.
		661
437	=item blessed objects	662	=item blessed objects
438		663
439	Blessed objects are not allowed. JSON::XS currently tries to encode their	664	Blessed objects are not allowed. JSON::XS currently tries to encode their
440	underlying representation (hash- or arrayref), but this behaviour might	665	underlying representation (hash- or arrayref), but this behaviour might
441	change in future versions.	666	change in future versions.
…		…
562		787
563	Does not check input for validity.	788	Does not check input for validity.
564		789
565	=back	790	=back
566		791
		792
		793	=head2 JSON and YAML
		794
		795	You often hear that JSON is a subset (or a close subset) of YAML. This is,
		796	however, a mass hysteria and very far from the truth. In general, there is
		797	no way to configure JSON::XS to output a data structure as valid YAML.
		798
		799	If you really must use JSON::XS to generate YAML, you should use this
		800	algorithm (subject to change in future versions):
		801
		802	my $to_yaml = JSON::XS->new->utf8->space_after (1);
		803	my $yaml = $to_yaml->encode ($ref) . "\n";
		804
		805	This will usually generate JSON texts that also parse as valid
		806	YAML. Please note that YAML has hardcoded limits on (simple) object key
		807	lengths that JSON doesn't have, so you should make sure that your hash
		808	keys are noticably shorter than the 1024 characters YAML allows.
		809
		810	There might be other incompatibilities that I am not aware of. In general
		811	you should not try to generate YAML with a JSON generator or vice versa,
		812	or try to parse JSON with a YAML parser or vice versa: chances are high
		813	that you will run into severe interoperability problems.
		814
		815
567	=head2 SPEED	816	=head2 SPEED
568		817
569	It seems that JSON::XS is surprisingly fast, as shown in the following	818	It seems that JSON::XS is surprisingly fast, as shown in the following
570	tables. They have been generated with the help of the C<eg/bench> program	819	tables. They have been generated with the help of the C<eg/bench> program
571	in the JSON::XS distribution, to make it easy to compare on your own	820	in the JSON::XS distribution, to make it easy to compare on your own
572	system.	821	system.
573		822
574	First comes a comparison between various modules using a very short JSON	823	First comes a comparison between various modules using a very short
575	string:	824	single-line JSON string:
576		825
577	{"method": "handleMessage", "params": ["user1", "we were just talking"], "id": null}	826	{"method": "handleMessage", "params": ["user1", "we were just talking"], \
		827	"id": null, "array":[1,11,234,-5,1e5,1e7, true, false]}
578		828
579	It shows the number of encodes/decodes per second (JSON::XS uses the	829	It shows the number of encodes/decodes per second (JSON::XS uses
580	functional interface, while JSON::XS/2 uses the OO interface with	830	the functional interface, while JSON::XS/2 uses the OO interface
581	pretty-printing and hashkey sorting enabled). Higher is better:	831	with pretty-printing and hashkey sorting enabled, JSON::XS/3 enables
		832	shrink). Higher is better:
582		833
		834	Storable \| 15779.925 \| 14169.946 \|
		835	-----------+------------+------------+
583	module \| encode \| decode \|	836	module \| encode \| decode \|
584	-----------\|------------\|------------\|	837	-----------\|------------\|------------\|
585	JSON \| 11488.516 \| 7823.035 \|	838	JSON \| 4990.842 \| 4088.813 \|
586	JSON::DWIW \| 94708.054 \| 129094.260 \|	839	JSON::DWIW \| 51653.990 \| 71575.154 \|
587	JSON::PC \| 63884.157 \| 128528.212 \|	840	JSON::PC \| 65948.176 \| 74631.744 \|
588	JSON::Syck \| 34898.677 \| 42096.911 \|	841	JSON::PP \| 8931.652 \| 3817.168 \|
589	JSON::XS \| 654027.064 \| 396423.669 \|	842	JSON::Syck \| 24877.248 \| 27776.848 \|
590	JSON::XS/2 \| 371564.190 \| 371725.613 \|	843	JSON::XS \| 388361.481 \| 227951.304 \|
		844	JSON::XS/2 \| 227951.304 \| 218453.333 \|
		845	JSON::XS/3 \| 338250.323 \| 218453.333 \|
		846	Storable \| 16500.016 \| 135300.129 \|
591	-----------+------------+------------+	847	-----------+------------+------------+
592		848
593	That is, JSON::XS is more than six times faster than JSON::DWIW on	849	That is, JSON::XS is about five times faster than JSON::DWIW on encoding,
594	encoding, more than three times faster on decoding, and about thirty times	850	about three times faster on decoding, and over fourty times faster
595	faster than JSON, even with pretty-printing and key sorting.	851	than JSON, even with pretty-printing and key sorting. It also compares
		852	favourably to Storable for small amounts of data.
596		853
597	Using a longer test string (roughly 18KB, generated from Yahoo! Locals	854	Using a longer test string (roughly 18KB, generated from Yahoo! Locals
598	search API (http://nanoref.com/yahooapis/mgPdGg):	855	search API (http://nanoref.com/yahooapis/mgPdGg):
599		856
600	module \| encode \| decode \|	857	module \| encode \| decode \|
601	-----------\|------------\|------------\|	858	-----------\|------------\|------------\|
602	JSON \| 273.023 \| 44.674 \|	859	JSON \| 55.260 \| 34.971 \|
603	JSON::DWIW \| 1089.383 \| 1145.704 \|	860	JSON::DWIW \| 825.228 \| 1082.513 \|
604	JSON::PC \| 3097.419 \| 2393.921 \|	861	JSON::PC \| 3571.444 \| 2394.829 \|
605	JSON::Syck \| 514.060 \| 843.053 \|	862	JSON::PP \| 210.987 \| 32.574 \|
606	JSON::XS \| 6479.668 \| 3636.364 \|	863	JSON::Syck \| 552.551 \| 787.544 \|
607	JSON::XS/2 \| 3774.221 \| 3599.124 \|	864	JSON::XS \| 5780.463 \| 4854.519 \|
		865	JSON::XS/2 \| 3869.998 \| 4798.975 \|
		866	JSON::XS/3 \| 5862.880 \| 4798.975 \|
		867	Storable \| 4445.002 \| 5235.027 \|
608	-----------+------------+------------+	868	-----------+------------+------------+
609		869
610	Again, JSON::XS leads by far.	870	Again, JSON::XS leads by far (except for Storable which non-surprisingly
		871	decodes faster).
611		872
612	On large strings containing lots of high unicode characters, some modules	873	On large strings containing lots of high unicode characters, some modules
613	(such as JSON::PC) seem to decode faster than JSON::XS, but the result	874	(such as JSON::PC) seem to decode faster than JSON::XS, but the result
614	will be broken due to missing (or wrong) unicode handling. Others refuse	875	will be broken due to missing (or wrong) unicode handling. Others refuse
615	to decode or encode properly, so it was impossible to prepare a fair	876	to decode or encode properly, so it was impossible to prepare a fair
…		…
628	Second, you need to avoid resource-starving attacks. That means you should	889	Second, you need to avoid resource-starving attacks. That means you should
629	limit the size of JSON texts you accept, or make sure then when your	890	limit the size of JSON texts you accept, or make sure then when your
630	resources run out, thats just fine (e.g. by using a separate process that	891	resources run out, thats just fine (e.g. by using a separate process that
631	can crash safely). The size of a JSON text in octets or characters is	892	can crash safely). The size of a JSON text in octets or characters is
632	usually a good indication of the size of the resources required to decode	893	usually a good indication of the size of the resources required to decode
633	it into a Perl structure.	894	it into a Perl structure. While JSON::XS can check the size of the JSON
		895	text, it might be too late when you already have it in memory, so you
		896	might want to check the size before you accept the string.
634		897
635	Third, JSON::XS recurses using the C stack when decoding objects and	898	Third, JSON::XS recurses using the C stack when decoding objects and
636	arrays. The C stack is a limited resource: for instance, on my amd64	899	arrays. The C stack is a limited resource: for instance, on my amd64
637	machine with 8MB of stack size I can decode around 180k nested arrays but	900	machine with 8MB of stack size I can decode around 180k nested arrays but
638	only 14k nested JSON objects (due to perl itself recursing deeply on croak	901	only 14k nested JSON objects (due to perl itself recursing deeply on croak
…		…
643		906
644	And last but least, something else could bomb you that I forgot to think	907	And last but least, something else could bomb you that I forgot to think
645	of. In that case, you get to keep the pieces. I am always open for hints,	908	of. In that case, you get to keep the pieces. I am always open for hints,
646	though...	909	though...
647		910
		911	If you are using JSON::XS to return packets to consumption
		912	by javascript scripts in a browser you should have a look at
		913	L<http://jpsykes.com/47/practical-csrf-and-json-security> to see wether
		914	you are vulnerable to some common attack vectors (which really are browser
		915	design bugs, but it is still you who will have to deal with it, as major
		916	browser developers care only for features, not about doing security
		917	right).
		918
648		919
649	=head1 BUGS	920	=head1 BUGS
650		921
651	While the goal of this module is to be correct, that unfortunately does	922	While the goal of this module is to be correct, that unfortunately does
652	not mean its bug-free, only that I think its design is bug-free. It is	923	not mean its bug-free, only that I think its design is bug-free. It is
653	still relatively early in its development. If you keep reporting bugs they	924	still relatively early in its development. If you keep reporting bugs they
654	will be fixed swiftly, though.	925	will be fixed swiftly, though.
655		926
656	=cut	927	=cut
657		928
		929	our $true = do { bless \(my $dummy = 1), "JSON::XS::Boolean" };
		930	our $false = do { bless \(my $dummy = 0), "JSON::XS::Boolean" };
		931
658	sub true() { \1 }	932	sub true() { $true }
659	sub false() { \0 }	933	sub false() { $false }
		934
		935	sub is_bool($) {
		936	UNIVERSAL::isa $_[0], "JSON::XS::Boolean"
		937	# or UNIVERSAL::isa $_[0], "JSON::Literal"
		938	}
		939
		940	XSLoader::load "JSON::XS", $VERSION;
		941
		942	package JSON::XS::Boolean;
		943
		944	use overload
		945	"0+" => sub { ${$_[0]} },
		946	"++" => sub { $_[0] = ${$_[0]} + 1 },
		947	"--" => sub { $_[0] = ${$_[0]} - 1 },
		948	fallback => 1;
660		949
661	1;	950	1;
662		951
663	=head1 AUTHOR	952	=head1 AUTHOR
664		953

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Comparing JSON-XS/XS.pm (file contents): Revision 1.31 by root, Wed Apr 11 12:23:02 2007 UTC vs. Revision 1.59 by root, Mon Aug 27 01:49:01 2007 UTC

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Comparing JSON-XS/XS.pm (file contents):
Revision 1.31 by root, Wed Apr 11 12:23:02 2007 UTC vs.
Revision 1.59 by root, Mon Aug 27 01:49:01 2007 UTC