[ViewVC] Diff of: cvs/JSON-XS/README

Comparing JSON-XS/README (file contents):
Revision 1.8 by root, Sun Mar 25 22:11:06 2007 UTC vs.
Revision 1.16 by root, Thu Jul 26 11:33:35 2007 UTC

…		…
7	# exported functions, they croak on error	7	# exported functions, they croak on error
8	# and expect/generate UTF-8	8	# and expect/generate UTF-8
9		9
10	$utf8_encoded_json_text = to_json $perl_hash_or_arrayref;	10	$utf8_encoded_json_text = to_json $perl_hash_or_arrayref;
11	$perl_hash_or_arrayref = from_json $utf8_encoded_json_text;	11	$perl_hash_or_arrayref = from_json $utf8_encoded_json_text;
12
13	# objToJson and jsonToObj aliases to to_json and from_json
14	# are exported for compatibility to the JSON module,
15	# but should not be used in new code.
16		12
17	# OO-interface	13	# OO-interface
18		14
19	$coder = JSON::XS->new->ascii->pretty->allow_nonref;	15	$coder = JSON::XS->new->ascii->pretty->allow_nonref;
20	$pretty_printed_unencoded = $coder->encode ($perl_scalar);	16	$pretty_printed_unencoded = $coder->encode ($perl_scalar);
…		…
92		88
93	$perl_scalar = JSON::XS->new->utf8->decode ($json_text)	89	$perl_scalar = JSON::XS->new->utf8->decode ($json_text)
94		90
95	except being faster.	91	except being faster.
96		92
		93	$is_boolean = JSON::XS::is_bool $scalar
		94	Returns true if the passed scalar represents either JSON::XS::true
		95	or JSON::XS::false, two constants that act like 1 and 0,
		96	respectively and are used to represent JSON "true" and "false"
		97	values in Perl.
		98
		99	See MAPPING, below, for more information on how JSON values are
		100	mapped to Perl.
		101
97	OBJECT-ORIENTED INTERFACE	102	OBJECT-ORIENTED INTERFACE
98	The object oriented interface lets you configure your own encoding or	103	The object oriented interface lets you configure your own encoding or
99	decoding style, within the limits of supported formats.	104	decoding style, within the limits of supported formats.
100		105
101	$json = new JSON::XS	106	$json = new JSON::XS
…		…
112	$json = $json->ascii ([$enable])	117	$json = $json->ascii ([$enable])
113	If $enable is true (or missing), then the "encode" method will not	118	If $enable is true (or missing), then the "encode" method will not
114	generate characters outside the code range 0..127 (which is ASCII).	119	generate characters outside the code range 0..127 (which is ASCII).
115	Any unicode characters outside that range will be escaped using	120	Any unicode characters outside that range will be escaped using
116	either a single \uXXXX (BMP characters) or a double \uHHHH\uLLLLL	121	either a single \uXXXX (BMP characters) or a double \uHHHH\uLLLLL
117	escape sequence, as per RFC4627.	122	escape sequence, as per RFC4627. The resulting encoded JSON text can
		123	be treated as a native unicode string, an ascii-encoded,
		124	latin1-encoded or UTF-8 encoded string, or any other superset of
		125	ASCII.
118		126
119	If $enable is false, then the "encode" method will not escape	127	If $enable is false, then the "encode" method will not escape
120	Unicode characters unless required by the JSON syntax. This results	128	Unicode characters unless required by the JSON syntax or other
121	in a faster and more compact format.	129	flags. This results in a faster and more compact format.
		130
		131	The main use for this flag is to produce JSON texts that can be
		132	transmitted over a 7-bit channel, as the encoded JSON texts will not
		133	contain any 8 bit characters.
122		134
123	JSON::XS->new->ascii (1)->encode ([chr 0x10401])	135	JSON::XS->new->ascii (1)->encode ([chr 0x10401])
124	=> ["\ud801\udc01"]	136	=> ["\ud801\udc01"]
		137
		138	$json = $json->latin1 ([$enable])
		139	If $enable is true (or missing), then the "encode" method will
		140	encode the resulting JSON text as latin1 (or iso-8859-1), escaping
		141	any characters outside the code range 0..255. The resulting string
		142	can be treated as a latin1-encoded JSON text or a native unicode
		143	string. The "decode" method will not be affected in any way by this
		144	flag, as "decode" by default expects unicode, which is a strict
		145	superset of latin1.
		146
		147	If $enable is false, then the "encode" method will not escape
		148	Unicode characters unless required by the JSON syntax or other
		149	flags.
		150
		151	The main use for this flag is efficiently encoding binary data as
		152	JSON text, as most octets will not be escaped, resulting in a
		153	smaller encoded size. The disadvantage is that the resulting JSON
		154	text is encoded in latin1 (and must correctly be treated as such
		155	when storing and transfering), a rare encoding for JSON. It is
		156	therefore most useful when you want to store data structures known
		157	to contain binary data efficiently in files or databases, not when
		158	talking to other JSON encoders/decoders.
		159
		160	JSON::XS->new->latin1->encode (["\x{89}\x{abc}"]
		161	=> ["\x{89}\\u0abc"] # (perl syntax, U+abc escaped, U+89 not)
125		162
126	$json = $json->utf8 ([$enable])	163	$json = $json->utf8 ([$enable])
127	If $enable is true (or missing), then the "encode" method will	164	If $enable is true (or missing), then the "encode" method will
128	encode the JSON result into UTF-8, as required by many protocols,	165	encode the JSON result into UTF-8, as required by many protocols,
129	while the "decode" method expects to be handled an UTF-8-encoded	166	while the "decode" method expects to be handled an UTF-8-encoded
…		…
237	"allow_nonref", resulting in an invalid JSON text:	274	"allow_nonref", resulting in an invalid JSON text:
238		275
239	JSON::XS->new->allow_nonref->encode ("Hello, World!")	276	JSON::XS->new->allow_nonref->encode ("Hello, World!")
240	=> "Hello, World!"	277	=> "Hello, World!"
241		278
		279	$json = $json->allow_blessed ([$enable])
		280	If $enable is true (or missing), then the "encode" method will not
		281	barf when it encounters a blessed reference. Instead, the value of
		282	the convert_blessed option will decide wether "null"
		283	("convert_blessed" disabled or no "to_json" method found) or a
		284	representation of the object ("convert_blessed" enabled and
		285	"to_json" method found) is being encoded. Has no effect on "decode".
		286
		287	If $enable is false (the default), then "encode" will throw an
		288	exception when it encounters a blessed object.
		289
		290	$json = $json->convert_blessed ([$enable])
		291	If $enable is true (or missing), then "encode", upon encountering a
		292	blessed object, will check for the availability of the "TO_JSON"
		293	method on the object's class. If found, it will be called in scalar
		294	context and the resulting scalar will be encoded instead of the
		295	object. If no "TO_JSON" method is found, the value of
		296	"allow_blessed" will decide what to do.
		297
		298	The "TO_JSON" method may safely call die if it wants. If "TO_JSON"
		299	returns other blessed objects, those will be handled in the same
		300	way. "TO_JSON" must take care of not causing an endless recursion
		301	cycle (== crash) in this case. The name of "TO_JSON" was chosen
		302	because other methods called by the Perl core (== not by the user of
		303	the object) are usually in upper case letters and to avoid
		304	collisions with the "to_json" function.
		305
		306	This setting does not yet influence "decode" in any way, but in the
		307	future, global hooks might get installed that influence "decode" and
		308	are enabled by this setting.
		309
		310	If $enable is false, then the "allow_blessed" setting will decide
		311	what to do when a blessed object is found.
		312
		313	$json = $json->filter_json_object ([$coderef->($hashref)])
		314	When $coderef is specified, it will be called from "decode" each
		315	time it decodes a JSON object. The only argument is a reference to
		316	the newly-created hash. If the code references returns a single
		317	scalar (which need not be a reference), this value (i.e. a copy of
		318	that scalar to avoid aliasing) is inserted into the deserialised
		319	data structure. If it returns an empty list (NOTE: not "undef",
		320	which is a valid scalar), the original deserialised hash will be
		321	inserted. This setting can slow down decoding considerably.
		322
		323	When $coderef is omitted or undefined, any existing callback will be
		324	removed and "decode" will not change the deserialised hash in any
		325	way.
		326
		327	Example, convert all JSON objects into the integer 5:
		328
		329	my $js = JSON::XS->new->filter_json_object (sub { 5 });
		330	# returns [5]
		331	$js->decode ('[{}]')
		332	# throw an exception because allow_nonref is not enabled
		333	# so a lone 5 is not allowed.
		334	$js->decode ('{"a":1, "b":2}');
		335
		336	$json = $json->filter_json_single_key_object ($key [=>
		337	$coderef->($value)])
		338	Works remotely similar to "filter_json_object", but is only called
		339	for JSON objects having a single key named $key.
		340
		341	This $coderef is called before the one specified via
		342	"filter_json_object", if any. It gets passed the single value in the
		343	JSON object. If it returns a single value, it will be inserted into
		344	the data structure. If it returns nothing (not even "undef" but the
		345	empty list), the callback from "filter_json_object" will be called
		346	next, as if no single-key callback were specified.
		347
		348	If $coderef is omitted or undefined, the corresponding callback will
		349	be disabled. There can only ever be one callback for a given key.
		350
		351	As this callback gets called less often then the
		352	"filter_json_object" one, decoding speed will not usually suffer as
		353	much. Therefore, single-key objects make excellent targets to
		354	serialise Perl objects into, especially as single-key JSON objects
		355	are as close to the type-tagged value concept as JSON gets (its
		356	basically an ID/VALUE tuple). Of course, JSON does not support this
		357	in any way, so you need to make sure your data never looks like a
		358	serialised Perl hash.
		359
		360	Typical names for the single object key are "__class_whatever__", or
		361	"$__dollars_are_rarely_used__$" or "}ugly_brace_placement", or even
		362	things like "__class_md5sum(classname)__", to reduce the risk of
		363	clashing with real hashes.
		364
		365	Example, decode JSON objects of the form "{ "__widget__" => <id> }"
		366	into the corresponding $WIDGET{<id>} object:
		367
		368	# return whatever is in $WIDGET{5}:
		369	JSON::XS
		370	->new
		371	->filter_json_single_key_object (__widget__ => sub {
		372	$WIDGET{ $_[0] }
		373	})
		374	->decode ('{"__widget__": 5')
		375
		376	# this can be used with a TO_JSON method in some "widget" class
		377	# for serialisation to json:
		378	sub WidgetBase::TO_JSON {
		379	my ($self) = @_;
		380
		381	unless ($self->{id}) {
		382	$self->{id} = ..get..some..id..;
		383	$WIDGET{$self->{id}} = $self;
		384	}
		385
		386	{ __widget__ => $self->{id} }
		387	}
		388
242	$json = $json->shrink ([$enable])	389	$json = $json->shrink ([$enable])
243	Perl usually over-allocates memory a bit when allocating space for	390	Perl usually over-allocates memory a bit when allocating space for
244	strings. This flag optionally resizes strings generated by either	391	strings. This flag optionally resizes strings generated by either
245	"encode" or "decode" to their minimum size possible. This can save	392	"encode" or "decode" to their minimum size possible. This can save
246	memory when your JSON texts are either very very long or you have	393	memory when your JSON texts are either very very long or you have
247	many short strings. It will also try to downgrade any strings to	394	many short strings. It will also try to downgrade any strings to
248	octet-form if possible: perl stores strings internally either in an	395	octet-form if possible: perl stores strings internally either in an
249	encoding called UTF-X or in octet-form. The latter cannot store	396	encoding called UTF-X or in octet-form. The latter cannot store
250	everything but uses less space in general.	397	everything but uses less space in general (and some buggy Perl or C
		398	code might even rely on that internal representation being used).
		399
		400	The actual definition of what shrink does might change in future
		401	versions, but it will always try to save space at the expense of
		402	time.
251		403
252	If $enable is true (or missing), the string returned by "encode"	404	If $enable is true (or missing), the string returned by "encode"
253	will be shrunk-to-fit, while all strings generated by "decode" will	405	will be shrunk-to-fit, while all strings generated by "decode" will
254	also be shrunk-to-fit.	406	also be shrunk-to-fit.
255		407
…		…
260	converting strings that look like integers or floats into integers	412	converting strings that look like integers or floats into integers
261	or floats internally (there is no difference on the Perl level),	413	or floats internally (there is no difference on the Perl level),
262	saving space.	414	saving space.
263		415
264	$json = $json->max_depth ([$maximum_nesting_depth])	416	$json = $json->max_depth ([$maximum_nesting_depth])
265	Sets the maximum nesting level (default 8192) accepted while	417	Sets the maximum nesting level (default 512) accepted while encoding
266	encoding or decoding. If the JSON text or Perl data structure has an	418	or decoding. If the JSON text or Perl data structure has an equal or
267	equal or higher nesting level then this limit, then the encoder and	419	higher nesting level then this limit, then the encoder and decoder
268	decoder will stop and croak at that point.	420	will stop and croak at that point.
269		421
270	Nesting level is defined by number of hash- or arrayrefs that the	422	Nesting level is defined by number of hash- or arrayrefs that the
271	encoder needs to traverse to reach a given point or the number of	423	encoder needs to traverse to reach a given point or the number of
272	"{" or "[" characters without their matching closing parenthesis	424	"{" or "[" characters without their matching closing parenthesis
273	crossed to reach a given character in a string.	425	crossed to reach a given character in a string.
274		426
275	Setting the maximum depth to one disallows any nesting, so that	427	Setting the maximum depth to one disallows any nesting, so that
276	ensures that the object is only a single hash/object or array.	428	ensures that the object is only a single hash/object or array.
277		429
278	The argument to "max_depth" will be rounded up to the next nearest	430	The argument to "max_depth" will be rounded up to the next highest
279	power of two.	431	power of two. If no argument is given, the highest possible setting
		432	will be used, which is rarely useful.
		433
		434	See SECURITY CONSIDERATIONS, below, for more info on why this is
		435	useful.
		436
		437	$json = $json->max_size ([$maximum_string_size])
		438	Set the maximum length a JSON text may have (in bytes) where
		439	decoding is being attempted. The default is 0, meaning no limit.
		440	When "decode" is called on a string longer then this number of
		441	characters it will not attempt to decode the string but throw an
		442	exception. This setting has no effect on "encode" (yet).
		443
		444	The argument to "max_size" will be rounded up to the next highest
		445	power of two (so may be more than requested). If no argument is
		446	given, the limit check will be deactivated (same as when 0 is
		447	specified).
280		448
281	See SECURITY CONSIDERATIONS, below, for more info on why this is	449	See SECURITY CONSIDERATIONS, below, for more info on why this is
282	useful.	450	useful.
283		451
284	$json_text = $json->encode ($perl_scalar)	452	$json_text = $json->encode ($perl_scalar)
…		…
296		464
297	JSON numbers and strings become simple Perl scalars. JSON arrays	465	JSON numbers and strings become simple Perl scalars. JSON arrays
298	become Perl arrayrefs and JSON objects become Perl hashrefs. "true"	466	become Perl arrayrefs and JSON objects become Perl hashrefs. "true"
299	becomes 1, "false" becomes 0 and "null" becomes "undef".	467	becomes 1, "false" becomes 0 and "null" becomes "undef".
300		468
		469	($perl_scalar, $characters) = $json->decode_prefix ($json_text)
		470	This works like the "decode" method, but instead of raising an
		471	exception when there is trailing garbage after the first JSON
		472	object, it will silently stop parsing there and return the number of
		473	characters consumed so far.
		474
		475	This is useful if your JSON texts are not delimited by an outer
		476	protocol (which is not the brightest thing to do in the first place)
		477	and you need to know where the JSON text ends.
		478
		479	JSON::XS->new->decode_prefix ("[1] the tail")
		480	=> ([], 3)
		481
301	MAPPING	482	MAPPING
302	This section describes how JSON::XS maps Perl values to JSON values and	483	This section describes how JSON::XS maps Perl values to JSON values and
303	vice versa. These mappings are designed to "do the right thing" in most	484	vice versa. These mappings are designed to "do the right thing" in most
304	circumstances automatically, preserving round-tripping characteristics	485	circumstances automatically, preserving round-tripping characteristics
305	(what you put in comes out as something equivalent).	486	(what you put in comes out as something equivalent).
…		…
321	A JSON string becomes a string scalar in Perl - Unicode codepoints	502	A JSON string becomes a string scalar in Perl - Unicode codepoints
322	in JSON are represented by the same codepoints in the Perl string,	503	in JSON are represented by the same codepoints in the Perl string,
323	so no manual decoding is necessary.	504	so no manual decoding is necessary.
324		505
325	number	506	number
326	A JSON number becomes either an integer or numeric (floating point)	507	A JSON number becomes either an integer, numeric (floating point) or
327	scalar in perl, depending on its range and any fractional parts. On	508	string scalar in perl, depending on its range and any fractional
328	the Perl level, there is no difference between those as Perl handles	509	parts. On the Perl level, there is no difference between those as
329	all the conversion details, but an integer may take slightly less	510	Perl handles all the conversion details, but an integer may take
330	memory and might represent more values exactly than (floating point)	511	slightly less memory and might represent more values exactly than
331	numbers.	512	(floating point) numbers.
		513
		514	If the number consists of digits only, JSON::XS will try to
		515	represent it as an integer value. If that fails, it will try to
		516	represent it as a numeric (floating point) value if that is possible
		517	without loss of precision. Otherwise it will preserve the number as
		518	a string value.
		519
		520	Numbers containing a fractional or exponential part will always be
		521	represented as numeric (floating point) values, possibly at a loss
		522	of precision.
		523
		524	This might create round-tripping problems as numbers might become
		525	strings, but as Perl is typeless there is no other way to do it.
332		526
333	true, false	527	true, false
334	These JSON atoms become 0, 1, respectively. Information is lost in	528	These JSON atoms become "JSON::XS::true" and "JSON::XS::false",
335	this process. Future versions might represent those values	529	respectively. They are overloaded to act almost exactly like the
336	differently, but they will be guarenteed to act like these integers	530	numbers 1 and 0. You can check wether a scalar is a JSON boolean by
337	would normally in Perl.	531	using the "JSON::XS::is_bool" function.
338		532
339	null	533	null
340	A JSON null atom becomes "undef" in Perl.	534	A JSON null atom becomes "undef" in Perl.
341		535
342	PERL -> JSON	536	PERL -> JSON
…		…
344	truly typeless language, so we can only guess which JSON type is meant	538	truly typeless language, so we can only guess which JSON type is meant
345	by a Perl value.	539	by a Perl value.
346		540
347	hash references	541	hash references
348	Perl hash references become JSON objects. As there is no inherent	542	Perl hash references become JSON objects. As there is no inherent
349	ordering in hash keys, they will usually be encoded in a	543	ordering in hash keys (or JSON objects), they will usually be
350	pseudo-random order that can change between runs of the same program	544	encoded in a pseudo-random order that can change between runs of the
351	but stays generally the same within a single run of a program.	545	same program but stays generally the same within a single run of a
352	JSON::XS can optionally sort the hash keys (determined by the	546	program. JSON::XS can optionally sort the hash keys (determined by
353	canonical flag), so the same datastructure will serialise to the	547	the canonical flag), so the same datastructure will serialise to
354	same JSON text (given same settings and version of JSON::XS), but	548	the same JSON text (given same settings and version of JSON::XS),
355	this incurs a runtime overhead.	549	but this incurs a runtime overhead and is only rarely useful, e.g.
		550	when you want to compare some JSON text against another for
		551	equality.
356		552
357	array references	553	array references
358	Perl array references become JSON arrays.	554	Perl array references become JSON arrays.
		555
		556	other references
		557	Other unblessed references are generally not allowed and will cause
		558	an exception to be thrown, except for references to the integers 0
		559	and 1, which get turned into "false" and "true" atoms in JSON. You
		560	can also use "JSON::XS::false" and "JSON::XS::true" to improve
		561	readability.
		562
		563	to_json [\0,JSON::XS::true] # yields [false,true]
		564
		565	JSON::XS::true, JSON::XS::false
		566	These special values become JSON true and JSON false values,
		567	respectively. You cna alos use "\1" and "\0" directly if you want.
359		568
360	blessed objects	569	blessed objects
361	Blessed objects are not allowed. JSON::XS currently tries to encode	570	Blessed objects are not allowed. JSON::XS currently tries to encode
362	their underlying representation (hash- or arrayref), but this	571	their underlying representation (hash- or arrayref), but this
363	behaviour might change in future versions.	572	behaviour might change in future versions.
…		…
394	$x += 0; # numify it, ensuring it will be dumped as a number	603	$x += 0; # numify it, ensuring it will be dumped as a number
395	$x *= 1; # same thing, the choise is yours.	604	$x *= 1; # same thing, the choise is yours.
396		605
397	You can not currently output JSON booleans or force the type in	606	You can not currently output JSON booleans or force the type in
398	other, less obscure, ways. Tell me if you need this capability.	607	other, less obscure, ways. Tell me if you need this capability.
399
400	circular data structures
401	Those will be encoded until memory or stackspace runs out.
402		608
403	COMPARISON	609	COMPARISON
404	As already mentioned, this module was created because none of the	610	As already mentioned, this module was created because none of the
405	existing JSON modules could be made to work correctly. First I will	611	existing JSON modules could be made to work correctly. First I will
406	describe the problems (or pleasures) I encountered with various existing	612	describe the problems (or pleasures) I encountered with various existing
…		…
477	Does not generate valid JSON texts (key strings are often unquoted,	683	Does not generate valid JSON texts (key strings are often unquoted,
478	empty keys result in nothing being output)	684	empty keys result in nothing being output)
479		685
480	Does not check input for validity.	686	Does not check input for validity.
481		687
		688	JSON and YAML
		689	You often hear that JSON is a subset (or a close subset) of YAML. This
		690	is, however, a mass hysteria and very far from the truth. In general,
		691	there is no way to configure JSON::XS to output a data structure as
		692	valid YAML.
		693
		694	If you really must use JSON::XS to generate YAML, you should use this
		695	algorithm (subject to change in future versions):
		696
		697	my $to_yaml = JSON::XS->new->utf8->space_after (1);
		698	my $yaml = $to_yaml->encode ($ref) . "\n";
		699
		700	This will usually generate JSON texts that also parse as valid YAML.
		701	Please note that YAML has hardcoded limits on (simple) object key
		702	lengths that JSON doesn't have, so you should make sure that your hash
		703	keys are noticably shorter than the 1024 characters YAML allows.
		704
		705	There might be other incompatibilities that I am not aware of. In
		706	general you should not try to generate YAML with a JSON generator or
		707	vice versa, or try to parse JSON with a YAML parser or vice versa:
		708	chances are high that you will run into severe interoperability
		709	problems.
		710
482	SPEED	711	SPEED
483	It seems that JSON::XS is surprisingly fast, as shown in the following	712	It seems that JSON::XS is surprisingly fast, as shown in the following
484	tables. They have been generated with the help of the "eg/bench" program	713	tables. They have been generated with the help of the "eg/bench" program
485	in the JSON::XS distribution, to make it easy to compare on your own	714	in the JSON::XS distribution, to make it easy to compare on your own
486	system.	715	system.
487		716
488	First comes a comparison between various modules using a very short JSON	717	First comes a comparison between various modules using a very short
489	string:	718	single-line JSON string:
490		719
491	{"method": "handleMessage", "params": ["user1", "we were just talking"], "id": null}	720	{"method": "handleMessage", "params": ["user1", "we were just talking"], \
		721	"id": null, "array":[1,11,234,-5,1e5,1e7, true, false]}
492		722
493	It shows the number of encodes/decodes per second (JSON::XS uses the	723	It shows the number of encodes/decodes per second (JSON::XS uses the
494	functional interface, while JSON::XS/2 uses the OO interface with	724	functional interface, while JSON::XS/2 uses the OO interface with
495	pretty-printing and hashkey sorting enabled). Higher is better:	725	pretty-printing and hashkey sorting enabled, JSON::XS/3 enables shrink).
		726	Higher is better:
496		727
		728	Storable \| 15779.925 \| 14169.946 \|
		729	-----------+------------+------------+
497	module \| encode \| decode \|	730	module \| encode \| decode \|
498	-----------\|------------\|------------\|	731	-----------\|------------\|------------\|
499	JSON \| 11488.516 \| 7823.035 \|	732	JSON \| 4990.842 \| 4088.813 \|
500	JSON::DWIW \| 94708.054 \| 129094.260 \|	733	JSON::DWIW \| 51653.990 \| 71575.154 \|
501	JSON::PC \| 63884.157 \| 128528.212 \|	734	JSON::PC \| 65948.176 \| 74631.744 \|
		735	JSON::PP \| 8931.652 \| 3817.168 \|
502	JSON::Syck \| 34898.677 \| 42096.911 \|	736	JSON::Syck \| 24877.248 \| 27776.848 \|
503	JSON::XS \| 654027.064 \| 396423.669 \|	737	JSON::XS \| 388361.481 \| 227951.304 \|
504	JSON::XS/2 \| 371564.190 \| 371725.613 \|	738	JSON::XS/2 \| 227951.304 \| 218453.333 \|
		739	JSON::XS/3 \| 338250.323 \| 218453.333 \|
		740	Storable \| 16500.016 \| 135300.129 \|
505	-----------+------------+------------+	741	-----------+------------+------------+
506		742
507	That is, JSON::XS is more than six times faster than JSON::DWIW on	743	That is, JSON::XS is about five times faster than JSON::DWIW on
508	encoding, more than three times faster on decoding, and about thirty	744	encoding, about three times faster on decoding, and over fourty times
509	times faster than JSON, even with pretty-printing and key sorting.	745	faster than JSON, even with pretty-printing and key sorting. It also
		746	compares favourably to Storable for small amounts of data.
510		747
511	Using a longer test string (roughly 18KB, generated from Yahoo! Locals	748	Using a longer test string (roughly 18KB, generated from Yahoo! Locals
512	search API (http://nanoref.com/yahooapis/mgPdGg):	749	search API (http://nanoref.com/yahooapis/mgPdGg):
513		750
514	module \| encode \| decode \|	751	module \| encode \| decode \|
515	-----------\|------------\|------------\|	752	-----------\|------------\|------------\|
516	JSON \| 273.023 \| 44.674 \|	753	JSON \| 55.260 \| 34.971 \|
517	JSON::DWIW \| 1089.383 \| 1145.704 \|	754	JSON::DWIW \| 825.228 \| 1082.513 \|
518	JSON::PC \| 3097.419 \| 2393.921 \|	755	JSON::PC \| 3571.444 \| 2394.829 \|
519	JSON::Syck \| 514.060 \| 843.053 \|	756	JSON::PP \| 210.987 \| 32.574 \|
520	JSON::XS \| 6479.668 \| 3636.364 \|	757	JSON::Syck \| 552.551 \| 787.544 \|
521	JSON::XS/2 \| 3774.221 \| 3599.124 \|	758	JSON::XS \| 5780.463 \| 4854.519 \|
		759	JSON::XS/2 \| 3869.998 \| 4798.975 \|
		760	JSON::XS/3 \| 5862.880 \| 4798.975 \|
		761	Storable \| 4445.002 \| 5235.027 \|
522	-----------+------------+------------+	762	-----------+------------+------------+
523		763
524	Again, JSON::XS leads by far.	764	Again, JSON::XS leads by far (except for Storable which non-surprisingly
		765	decodes faster).
525		766
526	On large strings containing lots of high unicode characters, some	767	On large strings containing lots of high unicode characters, some
527	modules (such as JSON::PC) seem to decode faster than JSON::XS, but the	768	modules (such as JSON::PC) seem to decode faster than JSON::XS, but the
528	result will be broken due to missing (or wrong) unicode handling. Others	769	result will be broken due to missing (or wrong) unicode handling. Others
529	refuse to decode or encode properly, so it was impossible to prepare a	770	refuse to decode or encode properly, so it was impossible to prepare a
…		…
540	Second, you need to avoid resource-starving attacks. That means you	781	Second, you need to avoid resource-starving attacks. That means you
541	should limit the size of JSON texts you accept, or make sure then when	782	should limit the size of JSON texts you accept, or make sure then when
542	your resources run out, thats just fine (e.g. by using a separate	783	your resources run out, thats just fine (e.g. by using a separate
543	process that can crash safely). The size of a JSON text in octets or	784	process that can crash safely). The size of a JSON text in octets or
544	characters is usually a good indication of the size of the resources	785	characters is usually a good indication of the size of the resources
545	required to decode it into a Perl structure.	786	required to decode it into a Perl structure. While JSON::XS can check
		787	the size of the JSON text, it might be too late when you already have it
		788	in memory, so you might want to check the size before you accept the
		789	string.
546		790
547	Third, JSON::XS recurses using the C stack when decoding objects and	791	Third, JSON::XS recurses using the C stack when decoding objects and
548	arrays. The C stack is a limited resource: for instance, on my amd64	792	arrays. The C stack is a limited resource: for instance, on my amd64
549	machine with 8MB of stack size I can decode around 180k nested arrays	793	machine with 8MB of stack size I can decode around 180k nested arrays
550	but only 14k nested JSON objects. If that is exceeded, the program	794	but only 14k nested JSON objects (due to perl itself recursing deeply on
		795	croak to free the temporary). If that is exceeded, the program crashes.
551	crashes. Thats why the default nesting limit is set to 8192. If your	796	to be conservative, the default nesting limit is set to 512. If your
552	process has a smaller stack, you should adjust this setting accordingly	797	process has a smaller stack, you should adjust this setting accordingly
553	with the "max_depth" method.	798	with the "max_depth" method.
554		799
555	And last but least, something else could bomb you that I forgot to think	800	And last but least, something else could bomb you that I forgot to think
556	of. In that case, you get to keep the pieces. I am alway sopen for	801	of. In that case, you get to keep the pieces. I am always open for
557	hints, though...	802	hints, though...
		803
		804	If you are using JSON::XS to return packets to consumption by javascript
		805	scripts in a browser you should have a look at
		806	<http://jpsykes.com/47/practical-csrf-and-json-security> to see wether
		807	you are vulnerable to some common attack vectors (which really are
		808	browser design bugs, but it is still you who will have to deal with it,
		809	as major browser developers care only for features, not about doing
		810	security right).
558		811
559	BUGS	812	BUGS
560	While the goal of this module is to be correct, that unfortunately does	813	While the goal of this module is to be correct, that unfortunately does
561	not mean its bug-free, only that I think its design is bug-free. It is	814	not mean its bug-free, only that I think its design is bug-free. It is
562	still relatively early in its development. If you keep reporting bugs	815	still relatively early in its development. If you keep reporting bugs

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Comparing JSON-XS/README (file contents): Revision 1.8 by root, Sun Mar 25 22:11:06 2007 UTC vs. Revision 1.16 by root, Thu Jul 26 11:33:35 2007 UTC

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Comparing JSON-XS/README (file contents):
Revision 1.8 by root, Sun Mar 25 22:11:06 2007 UTC vs.
Revision 1.16 by root, Thu Jul 26 11:33:35 2007 UTC