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

Comparing JSON-XS/XS.pm (file contents):
Revision 1.138 by root, Wed Aug 1 19:04:41 2012 UTC vs.
Revision 1.148 by root, Tue Oct 29 00:19:45 2013 UTC

…		…
83	this module usually compares favourably in terms of speed, too.	83	this module usually compares favourably in terms of speed, too.
84		84
85	=item * simple to use	85	=item * simple to use
86		86
87	This module has both a simple functional interface as well as an object	87	This module has both a simple functional interface as well as an object
88	oriented interface interface.	88	oriented interface.
89		89
90	=item * reasonably versatile output formats	90	=item * reasonably versatile output formats
91		91
92	You can choose between the most compact guaranteed-single-line format	92	You can choose between the most compact guaranteed-single-line format
93	possible (nice for simple line-based protocols), a pure-ASCII format	93	possible (nice for simple line-based protocols), a pure-ASCII format
…		…
101		101
102	package JSON::XS;	102	package JSON::XS;
103		103
104	use common::sense;	104	use common::sense;
105		105
106	our $VERSION = '2.33';	106	our $VERSION = '3.0';
107	our @ISA = qw(Exporter);	107	our @ISA = qw(Exporter);
108		108
109	our @EXPORT = qw(encode_json decode_json to_json from_json);	109	our @EXPORT = qw(encode_json decode_json);
110
111	sub to_json($) {
112	require Carp;
113	Carp::croak ("JSON::XS::to_json has been renamed to encode_json, either downgrade to pre-2.0 versions of JSON::XS or rename the call");
114	}
115
116	sub from_json($) {
117	require Carp;
118	Carp::croak ("JSON::XS::from_json has been renamed to decode_json, either downgrade to pre-2.0 versions of JSON::XS or rename the call");
119	}
120		110
121	use Exporter;	111	use Exporter;
122	use XSLoader;	112	use XSLoader;
		113
		114	use Types::Serialiser ();
123		115
124	=head1 FUNCTIONAL INTERFACE	116	=head1 FUNCTIONAL INTERFACE
125		117
126	The following convenience methods are provided by this module. They are	118	The following convenience methods are provided by this module. They are
127	exported by default:	119	exported by default:
…		…
148	This function call is functionally identical to:	140	This function call is functionally identical to:
149		141
150	$perl_scalar = JSON::XS->new->utf8->decode ($json_text)	142	$perl_scalar = JSON::XS->new->utf8->decode ($json_text)
151		143
152	Except being faster.	144	Except being faster.
153
154	=item $is_boolean = JSON::XS::is_bool $scalar
155
156	Returns true if the passed scalar represents either JSON::XS::true or
157	JSON::XS::false, two constants that act like C<1> and C<0>, respectively
158	and are used to represent JSON C<true> and C<false> values in Perl.
159
160	See MAPPING, below, for more information on how JSON values are mapped to
161	Perl.
162		145
163	=back	146	=back
164		147
165		148
166	=head1 A FEW NOTES ON UNICODE AND PERL	149	=head1 A FEW NOTES ON UNICODE AND PERL
…		…
432	If C<$enable> is true (or missing), then the C<encode> method will output JSON objects	415	If C<$enable> is true (or missing), then the C<encode> method will output JSON objects
433	by sorting their keys. This is adding a comparatively high overhead.	416	by sorting their keys. This is adding a comparatively high overhead.
434		417
435	If C<$enable> is false, then the C<encode> method will output key-value	418	If C<$enable> is false, then the C<encode> method will output key-value
436	pairs in the order Perl stores them (which will likely change between runs	419	pairs in the order Perl stores them (which will likely change between runs
437	of the same script).	420	of the same script, and can change even within the same run from 5.18
		421	onwards).
438		422
439	This option is useful if you want the same data structure to be encoded as	423	This option is useful if you want the same data structure to be encoded as
440	the same JSON text (given the same overall settings). If it is disabled,	424	the same JSON text (given the same overall settings). If it is disabled,
441	the same hash might be encoded differently even if contains the same data,	425	the same hash might be encoded differently even if contains the same data,
442	as key-value pairs have no inherent ordering in Perl.	426	as key-value pairs have no inherent ordering in Perl.
…		…
483		467
484	=item $json = $json->allow_blessed ([$enable])	468	=item $json = $json->allow_blessed ([$enable])
485		469
486	=item $enabled = $json->get_allow_blessed	470	=item $enabled = $json->get_allow_blessed
487		471
		472	See L<OBJECT SERIALISATION> for details.
		473
488	If C<$enable> is true (or missing), then the C<encode> method will not	474	If C<$enable> is true (or missing), then the C<encode> method will not
489	barf when it encounters a blessed reference. Instead, the value of the	475	barf when it encounters a blessed reference that it cannot convert
490	B<convert_blessed> option will decide whether C<null> (C<convert_blessed>	476	otherwise. Instead, a JSON C<null> value is encoded instead of the object.
491	disabled or no C<TO_JSON> method found) or a representation of the
492	object (C<convert_blessed> enabled and C<TO_JSON> method found) is being
493	encoded. Has no effect on C<decode>.
494		477
495	If C<$enable> is false (the default), then C<encode> will throw an	478	If C<$enable> is false (the default), then C<encode> will throw an
496	exception when it encounters a blessed object.	479	exception when it encounters a blessed object that it cannot convert
		480	otherwise.
		481
		482	This setting has no effect on C<decode>.
497		483
498	=item $json = $json->convert_blessed ([$enable])	484	=item $json = $json->convert_blessed ([$enable])
499		485
500	=item $enabled = $json->get_convert_blessed	486	=item $enabled = $json->get_convert_blessed
		487
		488	See L<OBJECT SERIALISATION> for details.
501		489
502	If C<$enable> is true (or missing), then C<encode>, upon encountering a	490	If C<$enable> is true (or missing), then C<encode>, upon encountering a
503	blessed object, will check for the availability of the C<TO_JSON> method	491	blessed object, will check for the availability of the C<TO_JSON> method
504	on the object's class. If found, it will be called in scalar context	492	on the object's class. If found, it will be called in scalar context and
505	and the resulting scalar will be encoded instead of the object. If no	493	the resulting scalar will be encoded instead of the object.
506	C<TO_JSON> method is found, the value of C<allow_blessed> will decide what
507	to do.
508		494
509	The C<TO_JSON> method may safely call die if it wants. If C<TO_JSON>	495	The C<TO_JSON> method may safely call die if it wants. If C<TO_JSON>
510	returns other blessed objects, those will be handled in the same	496	returns other blessed objects, those will be handled in the same
511	way. C<TO_JSON> must take care of not causing an endless recursion cycle	497	way. C<TO_JSON> must take care of not causing an endless recursion cycle
512	(== crash) in this case. The name of C<TO_JSON> was chosen because other	498	(== crash) in this case. The name of C<TO_JSON> was chosen because other
513	methods called by the Perl core (== not by the user of the object) are	499	methods called by the Perl core (== not by the user of the object) are
514	usually in upper case letters and to avoid collisions with any C<to_json>	500	usually in upper case letters and to avoid collisions with any C<to_json>
515	function or method.	501	function or method.
516		502
517	This setting does not yet influence C<decode> in any way, but in the	503	If C<$enable> is false (the default), then C<encode> will not consider
518	future, global hooks might get installed that influence C<decode> and are	504	this type of conversion.
519	enabled by this setting.
520		505
521	If C<$enable> is false, then the C<allow_blessed> setting will decide what	506	This setting has no effect on C<decode>.
522	to do when a blessed object is found.	507
		508	=item $json = $json->allow_tags ([$enable])
		509
		510	=item $enabled = $json->allow_tags
		511
		512	See L<OBJECT SERIALISATION> for details.
		513
		514	If C<$enable> is true (or missing), then C<encode>, upon encountering a
		515	blessed object, will check for the availability of the C<FREEZE> method on
		516	the object's class. If found, it will be used to serialise the object into
		517	a nonstandard tagged JSON value (that JSON decoders cannot decode).
		518
		519	It also causes C<decode> to parse such tagged JSON values and deserialise
		520	them via a call to the C<THAW> method.
		521
		522	If C<$enable> is false (the default), then C<encode> will not consider
		523	this type of conversion, and tagged JSON values will cause a parse error
		524	in C<decode>, as if tags were not part of the grammar.
523		525
524	=item $json = $json->filter_json_object ([$coderef->($hashref)])	526	=item $json = $json->filter_json_object ([$coderef->($hashref)])
525		527
526	When C<$coderef> is specified, it will be called from C<decode> each	528	When C<$coderef> is specified, it will be called from C<decode> each
527	time it decodes a JSON object. The only argument is a reference to the	529	time it decodes a JSON object. The only argument is a reference to the
…		…
666		668
667	See SECURITY CONSIDERATIONS, below, for more info on why this is useful.	669	See SECURITY CONSIDERATIONS, below, for more info on why this is useful.
668		670
669	=item $json_text = $json->encode ($perl_scalar)	671	=item $json_text = $json->encode ($perl_scalar)
670		672
671	Converts the given Perl data structure (a simple scalar or a reference	673	Converts the given Perl value or data structure to its JSON
672	to a hash or array) to its JSON representation. Simple scalars will be	674	representation. Croaks on error.
673	converted into JSON string or number sequences, while references to arrays
674	become JSON arrays and references to hashes become JSON objects. Undefined
675	Perl values (e.g. C<undef>) become JSON C<null> values. Neither C<true>
676	nor C<false> values will be generated.
677		675
678	=item $perl_scalar = $json->decode ($json_text)	676	=item $perl_scalar = $json->decode ($json_text)
679		677
680	The opposite of C<encode>: expects a JSON text and tries to parse it,	678	The opposite of C<encode>: expects a JSON text and tries to parse it,
681	returning the resulting simple scalar or reference. Croaks on error.	679	returning the resulting simple scalar or reference. Croaks on error.
682
683	JSON numbers and strings become simple Perl scalars. JSON arrays become
684	Perl arrayrefs and JSON objects become Perl hashrefs. C<true> becomes
685	C<1>, C<false> becomes C<0> and C<null> becomes C<undef>.
686		680
687	=item ($perl_scalar, $characters) = $json->decode_prefix ($json_text)	681	=item ($perl_scalar, $characters) = $json->decode_prefix ($json_text)
688		682
689	This works like the C<decode> method, but instead of raising an exception	683	This works like the C<decode> method, but instead of raising an exception
690	when there is trailing garbage after the first JSON object, it will	684	when there is trailing garbage after the first JSON object, it will
691	silently stop parsing there and return the number of characters consumed	685	silently stop parsing there and return the number of characters consumed
692	so far.	686	so far.
693		687
694	This is useful if your JSON texts are not delimited by an outer protocol	688	This is useful if your JSON texts are not delimited by an outer protocol
695	(which is not the brightest thing to do in the first place) and you need
696	to know where the JSON text ends.	689	and you need to know where the JSON text ends.
697		690
698	JSON::XS->new->decode_prefix ("[1] the tail")	691	JSON::XS->new->decode_prefix ("[1] the tail")
699	=> ([], 3)	692	=> ([], 3)
700		693
701	=back	694	=back
…		…
740		733
741	If the method is called in scalar context, then it will try to extract	734	If the method is called in scalar context, then it will try to extract
742	exactly I<one> JSON object. If that is successful, it will return this	735	exactly I<one> JSON object. If that is successful, it will return this
743	object, otherwise it will return C<undef>. If there is a parse error,	736	object, otherwise it will return C<undef>. If there is a parse error,
744	this method will croak just as C<decode> would do (one can then use	737	this method will croak just as C<decode> would do (one can then use
745	C<incr_skip> to skip the errornous part). This is the most common way of	738	C<incr_skip> to skip the erroneous part). This is the most common way of
746	using the method.	739	using the method.
747		740
748	And finally, in list context, it will try to extract as many objects	741	And finally, in list context, it will try to extract as many objects
749	from the stream as it can find and return them, or the empty list	742	from the stream as it can find and return them, or the empty list
750	otherwise. For this to work, there must be no separators between the JSON	743	otherwise. For this to work, there must be no separators between the JSON
…		…
779	C<incr_parse> died, in which case the input buffer and incremental parser	772	C<incr_parse> died, in which case the input buffer and incremental parser
780	state is left unchanged, to skip the text parsed so far and to reset the	773	state is left unchanged, to skip the text parsed so far and to reset the
781	parse state.	774	parse state.
782		775
783	The difference to C<incr_reset> is that only text until the parse error	776	The difference to C<incr_reset> is that only text until the parse error
784	occured is removed.	777	occurred is removed.
785		778
786	=item $json->incr_reset	779	=item $json->incr_reset
787		780
788	This completely resets the incremental parser, that is, after this call,	781	This completely resets the incremental parser, that is, after this call,
789	it will be as if the parser had never parsed anything.	782	it will be as if the parser had never parsed anything.
…		…
795	=back	788	=back
796		789
797	=head2 LIMITATIONS	790	=head2 LIMITATIONS
798		791
799	All options that affect decoding are supported, except	792	All options that affect decoding are supported, except
800	C<allow_nonref>. The reason for this is that it cannot be made to	793	C<allow_nonref>. The reason for this is that it cannot be made to work
801	work sensibly: JSON objects and arrays are self-delimited, i.e. you can concatenate	794	sensibly: JSON objects and arrays are self-delimited, i.e. you can
802	them back to back and still decode them perfectly. This does not hold true	795	concatenate them back to back and still decode them perfectly. This does
803	for JSON numbers, however.	796	not hold true for JSON numbers, however.
804		797
805	For example, is the string C<1> a single JSON number, or is it simply the	798	For example, is the string C<1> a single JSON number, or is it simply the
806	start of C<12>? Or is C<12> a single JSON number, or the concatenation	799	start of C<12>? Or is C<12> a single JSON number, or the concatenation
807	of C<1> and C<2>? In neither case you can tell, and this is why JSON::XS	800	of C<1> and C<2>? In neither case you can tell, and this is why JSON::XS
808	takes the conservative route and disallows this case.	801	takes the conservative route and disallows this case.
…		…
987	If the number consists of digits only, JSON::XS will try to represent	980	If the number consists of digits only, JSON::XS will try to represent
988	it as an integer value. If that fails, it will try to represent it as	981	it as an integer value. If that fails, it will try to represent it as
989	a numeric (floating point) value if that is possible without loss of	982	a numeric (floating point) value if that is possible without loss of
990	precision. Otherwise it will preserve the number as a string value (in	983	precision. Otherwise it will preserve the number as a string value (in
991	which case you lose roundtripping ability, as the JSON number will be	984	which case you lose roundtripping ability, as the JSON number will be
992	re-encoded toa JSON string).	985	re-encoded to a JSON string).
993		986
994	Numbers containing a fractional or exponential part will always be	987	Numbers containing a fractional or exponential part will always be
995	represented as numeric (floating point) values, possibly at a loss of	988	represented as numeric (floating point) values, possibly at a loss of
996	precision (in which case you might lose perfect roundtripping ability, but	989	precision (in which case you might lose perfect roundtripping ability, but
997	the JSON number will still be re-encoded as a JSON number).	990	the JSON number will still be re-encoded as a JSON number).
998		991
999	Note that precision is not accuracy - binary floating point values cannot	992	Note that precision is not accuracy - binary floating point values cannot
1000	represent most decimal fractions exactly, and when converting from and to	993	represent most decimal fractions exactly, and when converting from and to
1001	floating point, JSON::XS only guarantees precision up to but not including	994	floating point, JSON::XS only guarantees precision up to but not including
1002	the leats significant bit.	995	the least significant bit.
1003		996
1004	=item true, false	997	=item true, false
1005		998
1006	These JSON atoms become C<JSON::XS::true> and C<JSON::XS::false>,	999	These JSON atoms become C<Types::Serialiser::true> and
1007	respectively. They are overloaded to act almost exactly like the numbers	1000	C<Types::Serialiser::false>, respectively. They are overloaded to act
1008	C<1> and C<0>. You can check whether a scalar is a JSON boolean by using	1001	almost exactly like the numbers C<1> and C<0>. You can check whether
1009	the C<JSON::XS::is_bool> function.	1002	a scalar is a JSON boolean by using the C<Types::Serialiser::is_bool>
		1003	function (after C<use Types::Serialier>, of course).
1010		1004
1011	=item null	1005	=item null
1012		1006
1013	A JSON null atom becomes C<undef> in Perl.	1007	A JSON null atom becomes C<undef> in Perl.
		1008
		1009	=item shell-style comments (C<< # I<text> >>)
		1010
		1011	As a nonstandard extension to the JSON syntax that is enabled by the
		1012	C<relaxed> setting, shell-style comments are allowed. They can start
		1013	anywhere outside strings and go till the end of the line.
		1014
		1015	=item tagged values (C<< (I<tag>)I<value> >>).
		1016
		1017	Another nonstandard extension to the JSON syntax, enabled with the
		1018	C<allow_tags> setting, are tagged values. In this implementation, the
		1019	I<tag> must be a perl package/class name encoded as a JSON string, and the
		1020	I<value> must be a JSON array encoding optional constructor arguments.
		1021
		1022	See L<OBJECT SERIALISATION>, below, for details.
1014		1023
1015	=back	1024	=back
1016		1025
1017		1026
1018	=head2 PERL -> JSON	1027	=head2 PERL -> JSON
…		…
1023		1032
1024	=over 4	1033	=over 4
1025		1034
1026	=item hash references	1035	=item hash references
1027		1036
1028	Perl hash references become JSON objects. As there is no inherent ordering	1037	Perl hash references become JSON objects. As there is no inherent
1029	in hash keys (or JSON objects), they will usually be encoded in a	1038	ordering in hash keys (or JSON objects), they will usually be encoded
1030	pseudo-random order that can change between runs of the same program but	1039	in a pseudo-random order. JSON::XS can optionally sort the hash keys
1031	stays generally the same within a single run of a program. JSON::XS can	1040	(determined by the I<canonical> flag), so the same datastructure will
1032	optionally sort the hash keys (determined by the I<canonical> flag), so	1041	serialise to the same JSON text (given same settings and version of
1033	the same datastructure will serialise to the same JSON text (given same	1042	JSON::XS), but this incurs a runtime overhead and is only rarely useful,
1034	settings and version of JSON::XS), but this incurs a runtime overhead	1043	e.g. when you want to compare some JSON text against another for equality.
1035	and is only rarely useful, e.g. when you want to compare some JSON text
1036	against another for equality.
1037		1044
1038	=item array references	1045	=item array references
1039		1046
1040	Perl array references become JSON arrays.	1047	Perl array references become JSON arrays.
1041		1048
1042	=item other references	1049	=item other references
1043		1050
1044	Other unblessed references are generally not allowed and will cause an	1051	Other unblessed references are generally not allowed and will cause an
1045	exception to be thrown, except for references to the integers C<0> and	1052	exception to be thrown, except for references to the integers C<0> and
1046	C<1>, which get turned into C<false> and C<true> atoms in JSON. You can	1053	C<1>, which get turned into C<false> and C<true> atoms in JSON.
1047	also use C<JSON::XS::false> and C<JSON::XS::true> to improve readability.
1048		1054
		1055	Since C<JSON::XS> uses the boolean model from L<Types::Serialiser>, you
		1056	can also C<use Types::Serialiser> and then use C<Types::Serialiser::false>
		1057	and C<Types::Serialiser::true> to improve readability.
		1058
		1059	use Types::Serialiser;
1049	encode_json [\0, JSON::XS::true] # yields [false,true]	1060	encode_json [\0, Types::Serialiser::true] # yields [false,true]
1050		1061
1051	=item JSON::XS::true, JSON::XS::false	1062	=item Types::Serialiser::true, Types::Serialiser::false
1052		1063
1053	These special values become JSON true and JSON false values,	1064	These special values from the L<Types::Serialiser> module become JSON true
1054	respectively. You can also use C<\1> and C<\0> directly if you want.	1065	and JSON false values, respectively. You can also use C<\1> and C<\0>
		1066	directly if you want.
1055		1067
1056	=item blessed objects	1068	=item blessed objects
1057		1069
1058	Blessed objects are not directly representable in JSON. See the	1070	Blessed objects are not directly representable in JSON, but C<JSON::XS>
1059	C<allow_blessed> and C<convert_blessed> methods on various options on	1071	allows various ways of handling objects. See L<OBJECT SERIALISATION>,
1060	how to deal with this: basically, you can choose between throwing an	1072	below, for details.
1061	exception, encoding the reference as if it weren't blessed, or provide
1062	your own serialiser method.
1063		1073
1064	=item simple scalars	1074	=item simple scalars
1065		1075
1066	Simple Perl scalars (any scalar that is not a reference) are the most	1076	Simple Perl scalars (any scalar that is not a reference) are the most
1067	difficult objects to encode: JSON::XS will encode undefined scalars as	1077	difficult objects to encode: JSON::XS will encode undefined scalars as
…		…
1104	infinities or NaN's - these cannot be represented in JSON, and it is an	1114	infinities or NaN's - these cannot be represented in JSON, and it is an
1105	error to pass those in.	1115	error to pass those in.
1106		1116
1107	=back	1117	=back
1108		1118
		1119	=head2 OBJECT SERIALISATION
		1120
		1121	As JSON cannot directly represent Perl objects, you have to choose between
		1122	a pure JSON representation (without the ability to deserialise the object
		1123	automatically again), and a nonstandard extension to the JSON syntax,
		1124	tagged values.
		1125
		1126	=head3 SERIALISATION
		1127
		1128	What happens when C<JSON::XS> encounters a Perl object depends on the
		1129	C<allow_blessed>, C<convert_blessed> and C<allow_tags> settings, which are
		1130	used in this order:
		1131
		1132	=over 4
		1133
		1134	=item 1. C<allow_tags> is enabled and object has a C<FREEZE> method.
		1135
		1136	In this case, C<JSON::XS> uses the L<Types::Serialiser> object
		1137	serialisation protocol to create a tagged JSON value, using a nonstandard
		1138	extension to the JSON syntax.
		1139
		1140	This works by invoking the C<FREEZE> method on the object, with the first
		1141	argument being the object to serialise, and the second argument being the
		1142	constant string C<JSON> to distinguish it from other serialisers.
		1143
		1144	The C<FREEZE> method can return any number of values (i.e. zero or
		1145	more). These values and the paclkage/classname of the object will then be
		1146	encoded as a tagged JSON value in the following format:
		1147
		1148	("classname")[FREEZE return values...]
		1149
		1150	For example, the hypothetical C<My::Object> C<FREEZE> method might use the
		1151	objects C<type> and C<id> members to encode the object:
		1152
		1153	sub My::Object::FREEZE {
		1154	my ($self, $serialiser) = @_;
		1155
		1156	($self->{type}, $self->{id})
		1157	}
		1158
		1159	=item 2. C<convert_blessed> is enabled and object has a C<TO_JSON> method.
		1160
		1161	In this case, the C<TO_JSON> method of the object is invoked in scalar
		1162	context. It must return a single scalar that can be directly encoded into
		1163	JSON. This scalar replaces the object in the JSON text.
		1164
		1165	For example, the following C<TO_JSON> method will convert all L<URI>
		1166	objects to JSON strings when serialised. The fatc that these values
		1167	originally were L<URI> objects is lost.
		1168
		1169	sub URI::TO_JSON {
		1170	my ($uri) = @_;
		1171	$uri->as_string
		1172	}
		1173
		1174	=item 3. C<allow_blessed> is enabled.
		1175
		1176	The object will be serialised as a JSON null value.
		1177
		1178	=item 4. none of the above
		1179
		1180	If none of the settings are enabled or the respective methods are missing,
		1181	C<JSON::XS> throws an exception.
		1182
		1183	=back
		1184
		1185	=head3 DESERIALISATION
		1186
		1187	For deserialisation there are only two cases to consider: either
		1188	nonstandard tagging was used, in which case C<allow_tags> decides,
		1189	or objects cannot be automatically be deserialised, in which
		1190	case you can use postprocessing or the C<filter_json_object> or
		1191	C<filter_json_single_key_object> callbacks to get some real objects our of
		1192	your JSON.
		1193
		1194	This section only considers the tagged value case: I a tagged JSON object
		1195	is encountered during decoding and C<allow_tags> is disabled, a parse
		1196	error will result (as if tagged values were not part of the grammar).
		1197
		1198	If C<allow_tags> is enabled, C<JSON::XS> will look up the C<THAW> method
		1199	of the package/classname used during serialisation (it will not attempt
		1200	to load the package as a Perl module). If there is no such method, the
		1201	decoding will fail with an error.
		1202
		1203	Otherwise, the C<THAW> method is invoked with the classname as first
		1204	argument, the constant string C<JSON> as second argument, and all the
		1205	values from the JSON array (the values originally returned by the
		1206	C<FREEZE> method) as remaining arguments.
		1207
		1208	The method must then return the object. While technically you can return
		1209	any Perl scalar, you might have to enable the C<enable_nonref> setting to
		1210	make that work in all cases, so better return an actual blessed reference.
		1211
		1212	As an example, let's implement a C<THAW> function that regenerates the
		1213	C<My::Object> from the C<FREEZE> example earlier:
		1214
		1215	sub My::Object::THAW {
		1216	my ($class, $serialiser, $type, $id) = @_;
		1217
		1218	$class->new (type => $type, id => $id)
		1219	}
		1220
1109		1221
1110	=head1 ENCODING/CODESET FLAG NOTES	1222	=head1 ENCODING/CODESET FLAG NOTES
1111		1223
1112	The interested reader might have seen a number of flags that signify	1224	The interested reader might have seen a number of flags that signify
1113	encodings or codesets - C<utf8>, C<latin1> and C<ascii>. There seems to be	1225	encodings or codesets - C<utf8>, C<latin1> and C<ascii>. There seems to be
…		…
1137	=item C<utf8> flag disabled	1249	=item C<utf8> flag disabled
1138		1250
1139	When C<utf8> is disabled (the default), then C<encode>/C<decode> generate	1251	When C<utf8> is disabled (the default), then C<encode>/C<decode> generate
1140	and expect Unicode strings, that is, characters with high ordinal Unicode	1252	and expect Unicode strings, that is, characters with high ordinal Unicode
1141	values (> 255) will be encoded as such characters, and likewise such	1253	values (> 255) will be encoded as such characters, and likewise such
1142	characters are decoded as-is, no canges to them will be done, except	1254	characters are decoded as-is, no changes to them will be done, except
1143	"(re-)interpreting" them as Unicode codepoints or Unicode characters,	1255	"(re-)interpreting" them as Unicode codepoints or Unicode characters,
1144	respectively (to Perl, these are the same thing in strings unless you do	1256	respectively (to Perl, these are the same thing in strings unless you do
1145	funny/weird/dumb stuff).	1257	funny/weird/dumb stuff).
1146		1258
1147	This is useful when you want to do the encoding yourself (e.g. when you	1259	This is useful when you want to do the encoding yourself (e.g. when you
…		…
1263	output for these property strings, e.g.:	1375	output for these property strings, e.g.:
1264		1376
1265	$json =~ s/"__proto__"\s*:/"__proto__renamed":/g;	1377	$json =~ s/"__proto__"\s*:/"__proto__renamed":/g;
1266		1378
1267	This works because C<__proto__> is not valid outside of strings, so every	1379	This works because C<__proto__> is not valid outside of strings, so every
1268	occurence of C<"__proto__"\s*:> must be a string used as property name.	1380	occurrence of C<"__proto__"\s*:> must be a string used as property name.
1269		1381
1270	If you know of other incompatibilities, please let me know.	1382	If you know of other incompatibilities, please let me know.
1271		1383
1272		1384
1273	=head2 JSON and YAML	1385	=head2 JSON and YAML
…		…
1435	are browser design bugs, but it is still you who will have to deal with	1547	are browser design bugs, but it is still you who will have to deal with
1436	it, as major browser developers care only for features, not about getting	1548	it, as major browser developers care only for features, not about getting
1437	security right).	1549	security right).
1438		1550
1439		1551
		1552	=head1 INTEROPERABILITY WITH OTHER MODULES
		1553
		1554	C<JSON::XS> uses the L<Types::Serialiser> module to provide boolean
		1555	constants. That means that the JSON true and false values will be
		1556	comaptible to true and false values of iother modules that do the same,
		1557	such as L<JSON::PP> and L<CBOR::XS>.
		1558
		1559
1440	=head1 THREADS	1560	=head1 THREADS
1441		1561
1442	This module is I<not> guaranteed to be thread safe and there are no	1562	This module is I<not> guaranteed to be thread safe and there are no
1443	plans to change this until Perl gets thread support (as opposed to the	1563	plans to change this until Perl gets thread support (as opposed to the
1444	horribly slow so-called "threads" which are simply slow and bloated	1564	horribly slow so-called "threads" which are simply slow and bloated
1445	process simulations - use fork, it's I<much> faster, cheaper, better).	1565	process simulations - use fork, it's I<much> faster, cheaper, better).
1446		1566
1447	(It might actually work, but you have been warned).	1567	(It might actually work, but you have been warned).
1448		1568
1449		1569
		1570	=head1 THE PERILS OF SETLOCALE
		1571
		1572	Sometimes people avoid the Perl locale support and directly call the
		1573	system's setlocale function with C<LC_ALL>.
		1574
		1575	This breaks both perl and modules such as JSON::XS, as stringification of
		1576	numbers no longer works correctly (e.g. C<$x = 0.1; print "$x"+1> might
		1577	print C<1>, and JSON::XS might output illegal JSON as JSON::XS relies on
		1578	perl to stringify numbers).
		1579
		1580	The solution is simple: don't call C<setlocale>, or use it for only those
		1581	categories you need, such as C<LC_MESSAGES> or C<LC_CTYPE>.
		1582
		1583	If you need C<LC_NUMERIC>, you should enable it only around the code that
		1584	actually needs it (avoiding stringification of numbers), and restore it
		1585	afterwards.
		1586
		1587
1450	=head1 BUGS	1588	=head1 BUGS
1451		1589
1452	While the goal of this module is to be correct, that unfortunately does	1590	While the goal of this module is to be correct, that unfortunately does
1453	not mean it's bug-free, only that I think its design is bug-free. If you	1591	not mean it's bug-free, only that I think its design is bug-free. If you
1454	keep reporting bugs they will be fixed swiftly, though.	1592	keep reporting bugs they will be fixed swiftly, though.
…		…
1456	Please refrain from using rt.cpan.org or any other bug reporting	1594	Please refrain from using rt.cpan.org or any other bug reporting
1457	service. I put the contact address into my modules for a reason.	1595	service. I put the contact address into my modules for a reason.
1458		1596
1459	=cut	1597	=cut
1460		1598
1461	our $true = do { bless \(my $dummy = 1), "JSON::XS::Boolean" };	1599	BEGIN {
1462	our $false = do { bless \(my $dummy = 0), "JSON::XS::Boolean" };	1600	*true = \$Types::Serialiser::true;
		1601	*true = \&Types::Serialiser::true;
		1602	*false = \$Types::Serialiser::false;
		1603	*false = \&Types::Serialiser::false;
		1604	*is_bool = \&Types::Serialiser::is_bool;
1463		1605
1464	sub true() { $true }	1606	JSON::XS::Boolean:: = Types::Serialiser::Boolean::;
1465	sub false() { $false }
1466
1467	sub is_bool($) {
1468	UNIVERSAL::isa $_[0], "JSON::XS::Boolean"
1469	# or UNIVERSAL::isa $_[0], "JSON::Literal"
1470	}	1607	}
1471		1608
1472	XSLoader::load "JSON::XS", $VERSION;	1609	XSLoader::load "JSON::XS", $VERSION;
1473
1474	package JSON::XS::Boolean;
1475
1476	use overload
1477	"0+" => sub { ${$_[0]} },
1478	"++" => sub { $_[0] = ${$_[0]} + 1 },
1479	"--" => sub { $_[0] = ${$_[0]} - 1 },
1480	fallback => 1;
1481
1482	1;
1483		1610
1484	=head1 SEE ALSO	1611	=head1 SEE ALSO
1485		1612
1486	The F<json_xs> command line utility for quick experiments.	1613	The F<json_xs> command line utility for quick experiments.
1487		1614
…		…
1490	Marc Lehmann <schmorp@schmorp.de>	1617	Marc Lehmann <schmorp@schmorp.de>
1491	http://home.schmorp.de/	1618	http://home.schmorp.de/
1492		1619
1493	=cut	1620	=cut
1494		1621
		1622	1
		1623

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Comparing JSON-XS/XS.pm (file contents): Revision 1.138 by root, Wed Aug 1 19:04:41 2012 UTC vs. Revision 1.148 by root, Tue Oct 29 00:19:45 2013 UTC

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Comparing JSON-XS/XS.pm (file contents):
Revision 1.138 by root, Wed Aug 1 19:04:41 2012 UTC vs.
Revision 1.148 by root, Tue Oct 29 00:19:45 2013 UTC