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

Comparing JSON-XS/XS.pm (file contents):
Revision 1.141 by root, Fri Oct 25 19:53:08 2013 UTC vs.
Revision 1.161 by root, Wed Nov 16 19:21:53 2016 UTC

…		…
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 = 2.34;	106	our $VERSION = 3.03;
107	our @ISA = qw(Exporter);	107	our @ISA = qw(Exporter);
108		108
109	our @EXPORT = qw(encode_json decode_json);	109	our @EXPORT = qw(encode_json decode_json);
110		110
111	use Exporter;	111	use Exporter;
112	use XSLoader;	112	use XSLoader;
		113
		114	use Types::Serialiser ();
113		115
114	=head1 FUNCTIONAL INTERFACE	116	=head1 FUNCTIONAL INTERFACE
115		117
116	The following convenience methods are provided by this module. They are	118	The following convenience methods are provided by this module. They are
117	exported by default:	119	exported by default:
…		…
138	This function call is functionally identical to:	140	This function call is functionally identical to:
139		141
140	$perl_scalar = JSON::XS->new->utf8->decode ($json_text)	142	$perl_scalar = JSON::XS->new->utf8->decode ($json_text)
141		143
142	Except being faster.	144	Except being faster.
143
144	=item $is_boolean = JSON::XS::is_bool $scalar
145
146	Returns true if the passed scalar represents either JSON::XS::true or
147	JSON::XS::false, two constants that act like C<1> and C<0>, respectively
148	and are used to represent JSON C<true> and C<false> values in Perl.
149
150	See MAPPING, below, for more information on how JSON values are mapped to
151	Perl.
152		145
153	=back	146	=back
154		147
155		148
156	=head1 A FEW NOTES ON UNICODE AND PERL	149	=head1 A FEW NOTES ON UNICODE AND PERL
…		…
411	[	404	[
412	1, # this comment not allowed in JSON	405	1, # this comment not allowed in JSON
413	# neither this one...	406	# neither this one...
414	]	407	]
415		408
		409	=item * literal ASCII TAB characters in strings
		410
		411	Literal ASCII TAB characters are now allowed in strings (and treated as
		412	C<\t>).
		413
		414	[
		415	"Hello\tWorld",
		416	"Hello<TAB>World", # literal <TAB> would not normally be allowed
		417	]
		418
416	=back	419	=back
417		420
418	=item $json = $json->canonical ([$enable])	421	=item $json = $json->canonical ([$enable])
419		422
420	=item $enabled = $json->get_canonical	423	=item $enabled = $json->get_canonical
…		…
474		477
475	=item $json = $json->allow_blessed ([$enable])	478	=item $json = $json->allow_blessed ([$enable])
476		479
477	=item $enabled = $json->get_allow_blessed	480	=item $enabled = $json->get_allow_blessed
478		481
		482	See L<OBJECT SERIALISATION> for details.
		483
479	If C<$enable> is true (or missing), then the C<encode> method will not	484	If C<$enable> is true (or missing), then the C<encode> method will not
480	barf when it encounters a blessed reference. Instead, the value of the	485	barf when it encounters a blessed reference that it cannot convert
481	B<convert_blessed> option will decide whether C<null> (C<convert_blessed>	486	otherwise. Instead, a JSON C<null> value is encoded instead of the object.
482	disabled or no C<TO_JSON> method found) or a representation of the
483	object (C<convert_blessed> enabled and C<TO_JSON> method found) is being
484	encoded. Has no effect on C<decode>.
485		487
486	If C<$enable> is false (the default), then C<encode> will throw an	488	If C<$enable> is false (the default), then C<encode> will throw an
487	exception when it encounters a blessed object.	489	exception when it encounters a blessed object that it cannot convert
		490	otherwise.
		491
		492	This setting has no effect on C<decode>.
488		493
489	=item $json = $json->convert_blessed ([$enable])	494	=item $json = $json->convert_blessed ([$enable])
490		495
491	=item $enabled = $json->get_convert_blessed	496	=item $enabled = $json->get_convert_blessed
		497
		498	See L<OBJECT SERIALISATION> for details.
492		499
493	If C<$enable> is true (or missing), then C<encode>, upon encountering a	500	If C<$enable> is true (or missing), then C<encode>, upon encountering a
494	blessed object, will check for the availability of the C<TO_JSON> method	501	blessed object, will check for the availability of the C<TO_JSON> method
495	on the object's class. If found, it will be called in scalar context	502	on the object's class. If found, it will be called in scalar context and
496	and the resulting scalar will be encoded instead of the object. If no	503	the resulting scalar will be encoded instead of the object.
497	C<TO_JSON> method is found, the value of C<allow_blessed> will decide what
498	to do.
499		504
500	The C<TO_JSON> method may safely call die if it wants. If C<TO_JSON>	505	The C<TO_JSON> method may safely call die if it wants. If C<TO_JSON>
501	returns other blessed objects, those will be handled in the same	506	returns other blessed objects, those will be handled in the same
502	way. C<TO_JSON> must take care of not causing an endless recursion cycle	507	way. C<TO_JSON> must take care of not causing an endless recursion cycle
503	(== crash) in this case. The name of C<TO_JSON> was chosen because other	508	(== crash) in this case. The name of C<TO_JSON> was chosen because other
504	methods called by the Perl core (== not by the user of the object) are	509	methods called by the Perl core (== not by the user of the object) are
505	usually in upper case letters and to avoid collisions with any C<to_json>	510	usually in upper case letters and to avoid collisions with any C<to_json>
506	function or method.	511	function or method.
507		512
508	This setting does not yet influence C<decode> in any way, but in the	513	If C<$enable> is false (the default), then C<encode> will not consider
509	future, global hooks might get installed that influence C<decode> and are	514	this type of conversion.
510	enabled by this setting.
511		515
512	If C<$enable> is false, then the C<allow_blessed> setting will decide what	516	This setting has no effect on C<decode>.
513	to do when a blessed object is found.	517
		518	=item $json = $json->allow_tags ([$enable])
		519
		520	=item $enabled = $json->allow_tags
		521
		522	See L<OBJECT SERIALISATION> for details.
		523
		524	If C<$enable> is true (or missing), then C<encode>, upon encountering a
		525	blessed object, will check for the availability of the C<FREEZE> method on
		526	the object's class. If found, it will be used to serialise the object into
		527	a nonstandard tagged JSON value (that JSON decoders cannot decode).
		528
		529	It also causes C<decode> to parse such tagged JSON values and deserialise
		530	them via a call to the C<THAW> method.
		531
		532	If C<$enable> is false (the default), then C<encode> will not consider
		533	this type of conversion, and tagged JSON values will cause a parse error
		534	in C<decode>, as if tags were not part of the grammar.
514		535
515	=item $json = $json->filter_json_object ([$coderef->($hashref)])	536	=item $json = $json->filter_json_object ([$coderef->($hashref)])
516		537
517	When C<$coderef> is specified, it will be called from C<decode> each	538	When C<$coderef> is specified, it will be called from C<decode> each
518	time it decodes a JSON object. The only argument is a reference to the	539	time it decodes a JSON object. The only argument is a reference to the
…		…
673	when there is trailing garbage after the first JSON object, it will	694	when there is trailing garbage after the first JSON object, it will
674	silently stop parsing there and return the number of characters consumed	695	silently stop parsing there and return the number of characters consumed
675	so far.	696	so far.
676		697
677	This is useful if your JSON texts are not delimited by an outer protocol	698	This is useful if your JSON texts are not delimited by an outer protocol
678	(which is not the brightest thing to do in the first place) and you need
679	to know where the JSON text ends.	699	and you need to know where the JSON text ends.
680		700
681	JSON::XS->new->decode_prefix ("[1] the tail")	701	JSON::XS->new->decode_prefix ("[1] the tail")
682	=> ([], 3)	702	=> ([1], 3)
683		703
684	=back	704	=back
685		705
686		706
687	=head1 INCREMENTAL PARSING	707	=head1 INCREMENTAL PARSING
…		…
728	C<incr_skip> to skip the erroneous part). This is the most common way of	748	C<incr_skip> to skip the erroneous part). This is the most common way of
729	using the method.	749	using the method.
730		750
731	And finally, in list context, it will try to extract as many objects	751	And finally, in list context, it will try to extract as many objects
732	from the stream as it can find and return them, or the empty list	752	from the stream as it can find and return them, or the empty list
733	otherwise. For this to work, there must be no separators between the JSON	753	otherwise. For this to work, there must be no separators (other than
734	objects or arrays, instead they must be concatenated back-to-back. If	754	whitespace) between the JSON objects or arrays, instead they must be
735	an error occurs, an exception will be raised as in the scalar context	755	concatenated back-to-back. If an error occurs, an exception will be
736	case. Note that in this case, any previously-parsed JSON texts will be	756	raised as in the scalar context case. Note that in this case, any
737	lost.	757	previously-parsed JSON texts will be lost.
738		758
739	Example: Parse some JSON arrays/objects in a given string and return	759	Example: Parse some JSON arrays/objects in a given string and return
740	them.	760	them.
741		761
742	my @objs = JSON::XS->new->incr_parse ("[5][7][1,2]");	762	my @objs = JSON::XS->new->incr_parse ("[5][7][1,2]");
…		…
749	all other circumstances you must not call this function (I mean it.	769	all other circumstances you must not call this function (I mean it.
750	although in simple tests it might actually work, it I<will> fail under	770	although in simple tests it might actually work, it I<will> fail under
751	real world conditions). As a special exception, you can also call this	771	real world conditions). As a special exception, you can also call this
752	method before having parsed anything.	772	method before having parsed anything.
753		773
		774	That means you can only use this function to look at or manipulate text
		775	before or after complete JSON objects, not while the parser is in the
		776	middle of parsing a JSON object.
		777
754	This function is useful in two cases: a) finding the trailing text after a	778	This function is useful in two cases: a) finding the trailing text after a
755	JSON object or b) parsing multiple JSON objects separated by non-JSON text	779	JSON object or b) parsing multiple JSON objects separated by non-JSON text
756	(such as commas).	780	(such as commas).
757		781
758	=item $json->incr_skip	782	=item $json->incr_skip
…		…
778	=back	802	=back
779		803
780	=head2 LIMITATIONS	804	=head2 LIMITATIONS
781		805
782	All options that affect decoding are supported, except	806	All options that affect decoding are supported, except
783	C<allow_nonref>. The reason for this is that it cannot be made to	807	C<allow_nonref>. The reason for this is that it cannot be made to work
784	work sensibly: JSON objects and arrays are self-delimited, i.e. you can concatenate	808	sensibly: JSON objects and arrays are self-delimited, i.e. you can
785	them back to back and still decode them perfectly. This does not hold true	809	concatenate them back to back and still decode them perfectly. This does
786	for JSON numbers, however.	810	not hold true for JSON numbers, however.
787		811
788	For example, is the string C<1> a single JSON number, or is it simply the	812	For example, is the string C<1> a single JSON number, or is it simply the
789	start of C<12>? Or is C<12> a single JSON number, or the concatenation	813	start of C<12>? Or is C<12> a single JSON number, or the concatenation
790	of C<1> and C<2>? In neither case you can tell, and this is why JSON::XS	814	of C<1> and C<2>? In neither case you can tell, and this is why JSON::XS
791	takes the conservative route and disallows this case.	815	takes the conservative route and disallows this case.
…		…
984	floating point, JSON::XS only guarantees precision up to but not including	1008	floating point, JSON::XS only guarantees precision up to but not including
985	the least significant bit.	1009	the least significant bit.
986		1010
987	=item true, false	1011	=item true, false
988		1012
989	These JSON atoms become C<JSON::XS::true> and C<JSON::XS::false>,	1013	These JSON atoms become C<Types::Serialiser::true> and
990	respectively. They are overloaded to act almost exactly like the numbers	1014	C<Types::Serialiser::false>, respectively. They are overloaded to act
991	C<1> and C<0>. You can check whether a scalar is a JSON boolean by using	1015	almost exactly like the numbers C<1> and C<0>. You can check whether
992	the C<JSON::XS::is_bool> function.	1016	a scalar is a JSON boolean by using the C<Types::Serialiser::is_bool>
		1017	function (after C<use Types::Serialier>, of course).
993		1018
994	=item null	1019	=item null
995		1020
996	A JSON null atom becomes C<undef> in Perl.	1021	A JSON null atom becomes C<undef> in Perl.
		1022
		1023	=item shell-style comments (C<< # I<text> >>)
		1024
		1025	As a nonstandard extension to the JSON syntax that is enabled by the
		1026	C<relaxed> setting, shell-style comments are allowed. They can start
		1027	anywhere outside strings and go till the end of the line.
		1028
		1029	=item tagged values (C<< (I<tag>)I<value> >>).
		1030
		1031	Another nonstandard extension to the JSON syntax, enabled with the
		1032	C<allow_tags> setting, are tagged values. In this implementation, the
		1033	I<tag> must be a perl package/class name encoded as a JSON string, and the
		1034	I<value> must be a JSON array encoding optional constructor arguments.
		1035
		1036	See L<OBJECT SERIALISATION>, below, for details.
997		1037
998	=back	1038	=back
999		1039
1000		1040
1001	=head2 PERL -> JSON	1041	=head2 PERL -> JSON
…		…
1006		1046
1007	=over 4	1047	=over 4
1008		1048
1009	=item hash references	1049	=item hash references
1010		1050
1011	Perl hash references become JSON objects. As there is no inherent ordering	1051	Perl hash references become JSON objects. As there is no inherent
1012	in hash keys (or JSON objects), they will usually be encoded in a	1052	ordering in hash keys (or JSON objects), they will usually be encoded
1013	pseudo-random order that can change between runs of the same program but	1053	in a pseudo-random order. JSON::XS can optionally sort the hash keys
1014	stays generally the same within a single run of a program. JSON::XS can	1054	(determined by the I<canonical> flag), so the same datastructure will
1015	optionally sort the hash keys (determined by the I<canonical> flag), so	1055	serialise to the same JSON text (given same settings and version of
1016	the same datastructure will serialise to the same JSON text (given same	1056	JSON::XS), but this incurs a runtime overhead and is only rarely useful,
1017	settings and version of JSON::XS), but this incurs a runtime overhead	1057	e.g. when you want to compare some JSON text against another for equality.
1018	and is only rarely useful, e.g. when you want to compare some JSON text
1019	against another for equality.
1020		1058
1021	=item array references	1059	=item array references
1022		1060
1023	Perl array references become JSON arrays.	1061	Perl array references become JSON arrays.
1024		1062
1025	=item other references	1063	=item other references
1026		1064
1027	Other unblessed references are generally not allowed and will cause an	1065	Other unblessed references are generally not allowed and will cause an
1028	exception to be thrown, except for references to the integers C<0> and	1066	exception to be thrown, except for references to the integers C<0> and
1029	C<1>, which get turned into C<false> and C<true> atoms in JSON. You can	1067	C<1>, which get turned into C<false> and C<true> atoms in JSON.
1030	also use C<JSON::XS::false> and C<JSON::XS::true> to improve readability.
1031		1068
		1069	Since C<JSON::XS> uses the boolean model from L<Types::Serialiser>, you
		1070	can also C<use Types::Serialiser> and then use C<Types::Serialiser::false>
		1071	and C<Types::Serialiser::true> to improve readability.
		1072
		1073	use Types::Serialiser;
1032	encode_json [\0, JSON::XS::true] # yields [false,true]	1074	encode_json [\0, Types::Serialiser::true] # yields [false,true]
1033		1075
1034	=item JSON::XS::true, JSON::XS::false	1076	=item Types::Serialiser::true, Types::Serialiser::false
1035		1077
1036	These special values become JSON true and JSON false values,	1078	These special values from the L<Types::Serialiser> module become JSON true
1037	respectively. You can also use C<\1> and C<\0> directly if you want.	1079	and JSON false values, respectively. You can also use C<\1> and C<\0>
		1080	directly if you want.
1038		1081
1039	=item blessed objects	1082	=item blessed objects
1040		1083
1041	Blessed objects are not directly representable in JSON. See the	1084	Blessed objects are not directly representable in JSON, but C<JSON::XS>
1042	C<allow_blessed> and C<convert_blessed> methods on various options on	1085	allows various ways of handling objects. See L<OBJECT SERIALISATION>,
1043	how to deal with this: basically, you can choose between throwing an	1086	below, for details.
1044	exception, encoding the reference as if it weren't blessed, or provide
1045	your own serialiser method.
1046		1087
1047	=item simple scalars	1088	=item simple scalars
1048		1089
1049	Simple Perl scalars (any scalar that is not a reference) are the most	1090	Simple Perl scalars (any scalar that is not a reference) are the most
1050	difficult objects to encode: JSON::XS will encode undefined scalars as	1091	difficult objects to encode: JSON::XS will encode undefined scalars as
…		…
1086	extensions to the floating point numbers of your platform, such as	1127	extensions to the floating point numbers of your platform, such as
1087	infinities or NaN's - these cannot be represented in JSON, and it is an	1128	infinities or NaN's - these cannot be represented in JSON, and it is an
1088	error to pass those in.	1129	error to pass those in.
1089		1130
1090	=back	1131	=back
		1132
		1133	=head2 OBJECT SERIALISATION
		1134
		1135	As JSON cannot directly represent Perl objects, you have to choose between
		1136	a pure JSON representation (without the ability to deserialise the object
		1137	automatically again), and a nonstandard extension to the JSON syntax,
		1138	tagged values.
		1139
		1140	=head3 SERIALISATION
		1141
		1142	What happens when C<JSON::XS> encounters a Perl object depends on the
		1143	C<allow_blessed>, C<convert_blessed> and C<allow_tags> settings, which are
		1144	used in this order:
		1145
		1146	=over 4
		1147
		1148	=item 1. C<allow_tags> is enabled and the object has a C<FREEZE> method.
		1149
		1150	In this case, C<JSON::XS> uses the L<Types::Serialiser> object
		1151	serialisation protocol to create a tagged JSON value, using a nonstandard
		1152	extension to the JSON syntax.
		1153
		1154	This works by invoking the C<FREEZE> method on the object, with the first
		1155	argument being the object to serialise, and the second argument being the
		1156	constant string C<JSON> to distinguish it from other serialisers.
		1157
		1158	The C<FREEZE> method can return any number of values (i.e. zero or
		1159	more). These values and the paclkage/classname of the object will then be
		1160	encoded as a tagged JSON value in the following format:
		1161
		1162	("classname")[FREEZE return values...]
		1163
		1164	e.g.:
		1165
		1166	("URI")["http://www.google.com/"]
		1167	("MyDate")[2013,10,29]
		1168	("ImageData::JPEG")["Z3...VlCg=="]
		1169
		1170	For example, the hypothetical C<My::Object> C<FREEZE> method might use the
		1171	objects C<type> and C<id> members to encode the object:
		1172
		1173	sub My::Object::FREEZE {
		1174	my ($self, $serialiser) = @_;
		1175
		1176	($self->{type}, $self->{id})
		1177	}
		1178
		1179	=item 2. C<convert_blessed> is enabled and the object has a C<TO_JSON> method.
		1180
		1181	In this case, the C<TO_JSON> method of the object is invoked in scalar
		1182	context. It must return a single scalar that can be directly encoded into
		1183	JSON. This scalar replaces the object in the JSON text.
		1184
		1185	For example, the following C<TO_JSON> method will convert all L<URI>
		1186	objects to JSON strings when serialised. The fatc that these values
		1187	originally were L<URI> objects is lost.
		1188
		1189	sub URI::TO_JSON {
		1190	my ($uri) = @_;
		1191	$uri->as_string
		1192	}
		1193
		1194	=item 3. C<allow_blessed> is enabled.
		1195
		1196	The object will be serialised as a JSON null value.
		1197
		1198	=item 4. none of the above
		1199
		1200	If none of the settings are enabled or the respective methods are missing,
		1201	C<JSON::XS> throws an exception.
		1202
		1203	=back
		1204
		1205	=head3 DESERIALISATION
		1206
		1207	For deserialisation there are only two cases to consider: either
		1208	nonstandard tagging was used, in which case C<allow_tags> decides,
		1209	or objects cannot be automatically be deserialised, in which
		1210	case you can use postprocessing or the C<filter_json_object> or
		1211	C<filter_json_single_key_object> callbacks to get some real objects our of
		1212	your JSON.
		1213
		1214	This section only considers the tagged value case: I a tagged JSON object
		1215	is encountered during decoding and C<allow_tags> is disabled, a parse
		1216	error will result (as if tagged values were not part of the grammar).
		1217
		1218	If C<allow_tags> is enabled, C<JSON::XS> will look up the C<THAW> method
		1219	of the package/classname used during serialisation (it will not attempt
		1220	to load the package as a Perl module). If there is no such method, the
		1221	decoding will fail with an error.
		1222
		1223	Otherwise, the C<THAW> method is invoked with the classname as first
		1224	argument, the constant string C<JSON> as second argument, and all the
		1225	values from the JSON array (the values originally returned by the
		1226	C<FREEZE> method) as remaining arguments.
		1227
		1228	The method must then return the object. While technically you can return
		1229	any Perl scalar, you might have to enable the C<enable_nonref> setting to
		1230	make that work in all cases, so better return an actual blessed reference.
		1231
		1232	As an example, let's implement a C<THAW> function that regenerates the
		1233	C<My::Object> from the C<FREEZE> example earlier:
		1234
		1235	sub My::Object::THAW {
		1236	my ($class, $serialiser, $type, $id) = @_;
		1237
		1238	$class->new (type => $type, id => $id)
		1239	}
1091		1240
1092		1241
1093	=head1 ENCODING/CODESET FLAG NOTES	1242	=head1 ENCODING/CODESET FLAG NOTES
1094		1243
1095	The interested reader might have seen a number of flags that signify	1244	The interested reader might have seen a number of flags that signify
…		…
1418	are browser design bugs, but it is still you who will have to deal with	1567	are browser design bugs, but it is still you who will have to deal with
1419	it, as major browser developers care only for features, not about getting	1568	it, as major browser developers care only for features, not about getting
1420	security right).	1569	security right).
1421		1570
1422		1571
		1572	=head1 "OLD" VS. "NEW" JSON (RFC 4627 VS. RFC 7159)
		1573
		1574	TL;DR: Due to security concerns, JSON::XS will not allow scalar data in
		1575	JSON texts by default - you need to create your own JSON::XS object and
		1576	enable C<allow_nonref>:
		1577
		1578
		1579	my $json = JSON::XS->new->allow_nonref;
		1580
		1581	$text = $json->encode ($data);
		1582	$data = $json->decode ($text);
		1583
		1584	The long version: JSON being an important and supposedly stable format,
		1585	the IETF standardised it as RFC 4627 in 2006. Unfortunately, the inventor
		1586	of JSON, Dougles Crockford, unilaterally changed the definition of JSON in
		1587	javascript. Rather than create a fork, the IETF decided to standardise the
		1588	new syntax (apparently, so Iw as told, without finding it very amusing).
		1589
		1590	The biggest difference between thed original JSON and the new JSON is that
		1591	the new JSON supports scalars (anything other than arrays and objects) at
		1592	the toplevel of a JSON text. While this is strictly backwards compatible
		1593	to older versions, it breaks a number of protocols that relied on sending
		1594	JSON back-to-back, and is a minor security concern.
		1595
		1596	For example, imagine you have two banks communicating, and on one side,
		1597	trhe JSON coder gets upgraded. Two messages, such as C<10> and C<1000>
		1598	might then be confused to mean C<101000>, something that couldn't happen
		1599	in the original JSON, because niether of these messages would be valid
		1600	JSON.
		1601
		1602	If one side accepts these messages, then an upgrade in the coder on either
		1603	side could result in this becoming exploitable.
		1604
		1605	This module has always allowed these messages as an optional extension, by
		1606	default disabled. The security concerns are the reason why the default is
		1607	still disabled, but future versions might/will likely upgrade to the newer
		1608	RFC as default format, so you are advised to check your implementation
		1609	and/or override the default with C<< ->allow_nonref (0) >> to ensure that
		1610	future versions are safe.
		1611
		1612
		1613	=head1 INTEROPERABILITY WITH OTHER MODULES
		1614
		1615	C<JSON::XS> uses the L<Types::Serialiser> module to provide boolean
		1616	constants. That means that the JSON true and false values will be
		1617	comaptible to true and false values of other modules that do the same,
		1618	such as L<JSON::PP> and L<CBOR::XS>.
		1619
		1620
		1621	=head1 INTEROPERABILITY WITH OTHER JSON DECODERS
		1622
		1623	As long as you only serialise data that can be directly expressed in JSON,
		1624	C<JSON::XS> is incapable of generating invalid JSON output (modulo bugs,
		1625	but C<JSON::XS> has found more bugs in the official JSON testsuite (1)
		1626	than the official JSON testsuite has found in C<JSON::XS> (0)).
		1627
		1628	When you have trouble decoding JSON generated by this module using other
		1629	decoders, then it is very likely that you have an encoding mismatch or the
		1630	other decoder is broken.
		1631
		1632	When decoding, C<JSON::XS> is strict by default and will likely catch all
		1633	errors. There are currently two settings that change this: C<relaxed>
		1634	makes C<JSON::XS> accept (but not generate) some non-standard extensions,
		1635	and C<allow_tags> will allow you to encode and decode Perl objects, at the
		1636	cost of not outputting valid JSON anymore.
		1637
		1638	=head2 TAGGED VALUE SYNTAX AND STANDARD JSON EN/DECODERS
		1639
		1640	When you use C<allow_tags> to use the extended (and also nonstandard and
		1641	invalid) JSON syntax for serialised objects, and you still want to decode
		1642	the generated When you want to serialise objects, you can run a regex
		1643	to replace the tagged syntax by standard JSON arrays (it only works for
		1644	"normal" package names without comma, newlines or single colons). First,
		1645	the readable Perl version:
		1646
		1647	# if your FREEZE methods return no values, you need this replace first:
		1648	$json =~ s/$ \s* (" (?: [^\\":,]+\|\\.\|::)* ") \s* $ \s* \[\s*\]/[$1]/gx;
		1649
		1650	# this works for non-empty constructor arg lists:
		1651	$json =~ s/$ \s* (" (?: [^\\":,]+\|\\.\|::)* ") \s* $ \s* \[/[$1,/gx;
		1652
		1653	And here is a less readable version that is easy to adapt to other
		1654	languages:
		1655
		1656	$json =~ s/$\s("([^\\":,]+\|\\.\|::)")\s$\s\[/[$1,/g;
		1657
		1658	Here is an ECMAScript version (same regex):
		1659
		1660	json = json.replace (/$\s("([^\\":,]+\|\\.\|::)")\s$\s\[/g, "[$1,");
		1661
		1662	Since this syntax converts to standard JSON arrays, it might be hard to
		1663	distinguish serialised objects from normal arrays. You can prepend a
		1664	"magic number" as first array element to reduce chances of a collision:
		1665
		1666	$json =~ s/$\s("([^\\":,]+\|\\.\|::)")\s$\s\[/["XU1peReLzT4ggEllLanBYq4G9VzliwKF",$1,/g;
		1667
		1668	And after decoding the JSON text, you could walk the data
		1669	structure looking for arrays with a first element of
		1670	C<XU1peReLzT4ggEllLanBYq4G9VzliwKF>.
		1671
		1672	The same approach can be used to create the tagged format with another
		1673	encoder. First, you create an array with the magic string as first member,
		1674	the classname as second, and constructor arguments last, encode it as part
		1675	of your JSON structure, and then:
		1676
		1677	$json =~ s/\[\s"XU1peReLzT4ggEllLanBYq4G9VzliwKF"\s,\s("([^\\":,]+\|\\.\|::)")\s*,/($1)[/g;
		1678
		1679	Again, this has some limitations - the magic string must not be encoded
		1680	with character escapes, and the constructor arguments must be non-empty.
		1681
		1682
		1683	=head1 RFC7159
		1684
		1685	Since this module was written, Google has written a new JSON RFC, RFC 7159
		1686	(and RFC7158). Unfortunately, this RFC breaks compatibility with both the
		1687	original JSON specification on www.json.org and RFC4627.
		1688
		1689	As far as I can see, you can get partial compatibility when parsing by
		1690	using C<< ->allow_nonref >>. However, consider the security implications
		1691	of doing so.
		1692
		1693	I haven't decided yet when to break compatibility with RFC4627 by default
		1694	(and potentially leave applications insecure) and change the default to
		1695	follow RFC7159, but application authors are well advised to call C<<
		1696	->allow_nonref(0) >> even if this is the current default, if they cannot
		1697	handle non-reference values, in preparation for the day when the default
		1698	will change.
		1699
		1700
1423	=head1 THREADS	1701	=head1 THREADS
1424		1702
1425	This module is I<not> guaranteed to be thread safe and there are no	1703	This module is I<not> guaranteed to be thread safe and there are no
1426	plans to change this until Perl gets thread support (as opposed to the	1704	plans to change this until Perl gets thread support (as opposed to the
1427	horribly slow so-called "threads" which are simply slow and bloated	1705	horribly slow so-called "threads" which are simply slow and bloated
…		…
1457	Please refrain from using rt.cpan.org or any other bug reporting	1735	Please refrain from using rt.cpan.org or any other bug reporting
1458	service. I put the contact address into my modules for a reason.	1736	service. I put the contact address into my modules for a reason.
1459		1737
1460	=cut	1738	=cut
1461		1739
1462	our $true = do { bless \(my $dummy = 1), "JSON::XS::Boolean" };	1740	BEGIN {
1463	our $false = do { bless \(my $dummy = 0), "JSON::XS::Boolean" };	1741	*true = \$Types::Serialiser::true;
		1742	*true = \&Types::Serialiser::true;
		1743	*false = \$Types::Serialiser::false;
		1744	*false = \&Types::Serialiser::false;
		1745	*is_bool = \&Types::Serialiser::is_bool;
1464		1746
1465	sub true() { $true }	1747	JSON::XS::Boolean:: = Types::Serialiser::Boolean::;
1466	sub false() { $false }
1467
1468	sub is_bool($) {
1469	UNIVERSAL::isa $_[0], "JSON::XS::Boolean"
1470	# or UNIVERSAL::isa $_[0], "JSON::Literal"
1471	}	1748	}
1472		1749
1473	XSLoader::load "JSON::XS", $VERSION;	1750	XSLoader::load "JSON::XS", $VERSION;
1474
1475	package JSON::XS::Boolean;
1476
1477	use overload
1478	"0+" => sub { ${$_[0]} },
1479	"++" => sub { $_[0] = ${$_[0]} + 1 },
1480	"--" => sub { $_[0] = ${$_[0]} - 1 },
1481	fallback => 1;
1482
1483	1;
1484		1751
1485	=head1 SEE ALSO	1752	=head1 SEE ALSO
1486		1753
1487	The F<json_xs> command line utility for quick experiments.	1754	The F<json_xs> command line utility for quick experiments.
1488		1755
…		…
1491	Marc Lehmann <schmorp@schmorp.de>	1758	Marc Lehmann <schmorp@schmorp.de>
1492	http://home.schmorp.de/	1759	http://home.schmorp.de/
1493		1760
1494	=cut	1761	=cut
1495		1762
		1763	1
		1764

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Comparing JSON-XS/XS.pm (file contents): Revision 1.141 by root, Fri Oct 25 19:53:08 2013 UTC vs. Revision 1.161 by root, Wed Nov 16 19:21:53 2016 UTC

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Comparing JSON-XS/XS.pm (file contents):
Revision 1.141 by root, Fri Oct 25 19:53:08 2013 UTC vs.
Revision 1.161 by root, Wed Nov 16 19:21:53 2016 UTC