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Comparing JSON-XS/XS.pm (file contents):
Revision 1.113 by root, Thu Nov 20 03:59:53 2008 UTC vs.
Revision 1.123 by root, Sat Aug 8 10:06:02 2009 UTC

99 99
100=cut 100=cut
101 101
102package JSON::XS; 102package JSON::XS;
103 103
104no warnings; 104use common::sense;
105use strict;
106 105
107our $VERSION = '2.231'; 106our $VERSION = '2.25';
108our @ISA = qw(Exporter); 107our @ISA = qw(Exporter);
109 108
110our @EXPORT = qw(encode_json decode_json to_json from_json); 109our @EXPORT = qw(encode_json decode_json to_json from_json);
111 110
112sub to_json($) { 111sub to_json($) {
441the same JSON text (given the same overall settings). If it is disabled, 440the same JSON text (given the same overall settings). If it is disabled,
442the same hash might be encoded differently even if contains the same data, 441the same hash might be encoded differently even if contains the same data,
443as key-value pairs have no inherent ordering in Perl. 442as key-value pairs have no inherent ordering in Perl.
444 443
445This setting has no effect when decoding JSON texts. 444This setting has no effect when decoding JSON texts.
445
446This setting has currently no effect on tied hashes.
446 447
447=item $json = $json->allow_nonref ([$enable]) 448=item $json = $json->allow_nonref ([$enable])
448 449
449=item $enabled = $json->get_allow_nonref 450=item $enabled = $json->get_allow_nonref
450 451
766JSON object or b) parsing multiple JSON objects separated by non-JSON text 767JSON object or b) parsing multiple JSON objects separated by non-JSON text
767(such as commas). 768(such as commas).
768 769
769=item $json->incr_skip 770=item $json->incr_skip
770 771
771This will reset the state of the incremental parser and will remove the 772This will reset the state of the incremental parser and will remove
772parsed text from the input buffer. This is useful after C<incr_parse> 773the parsed text from the input buffer so far. This is useful after
773died, in which case the input buffer and incremental parser state is left 774C<incr_parse> died, in which case the input buffer and incremental parser
774unchanged, to skip the text parsed so far and to reset the parse state. 775state is left unchanged, to skip the text parsed so far and to reset the
776parse state.
777
778The difference to C<incr_reset> is that only text until the parse error
779occured is removed.
775 780
776=item $json->incr_reset 781=item $json->incr_reset
777 782
778This completely resets the incremental parser, that is, after this call, 783This completely resets the incremental parser, that is, after this call,
779it will be as if the parser had never parsed anything. 784it will be as if the parser had never parsed anything.
780 785
781This is useful if you want ot repeatedly parse JSON objects and want to 786This is useful if you want to repeatedly parse JSON objects and want to
782ignore any trailing data, which means you have to reset the parser after 787ignore any trailing data, which means you have to reset the parser after
783each successful decode. 788each successful decode.
784 789
785=back 790=back
786 791
1179when your channel for JSON transfer is not 8-bit clean or the encoding 1184when your channel for JSON transfer is not 8-bit clean or the encoding
1180might be mangled in between (e.g. in mail), and works because ASCII is a 1185might be mangled in between (e.g. in mail), and works because ASCII is a
1181proper subset of most 8-bit and multibyte encodings in use in the world. 1186proper subset of most 8-bit and multibyte encodings in use in the world.
1182 1187
1183=back 1188=back
1189
1190
1191=head2 JSON and ECMAscript
1192
1193JSON syntax is based on how literals are represented in javascript (the
1194not-standardised predecessor of ECMAscript) which is presumably why it is
1195called "JavaScript Object Notation".
1196
1197However, JSON is not a subset (and also not a superset of course) of
1198ECMAscript (the standard) or javascript (whatever browsers actually
1199implement).
1200
1201If you want to use javascript's C<eval> function to "parse" JSON, you
1202might run into parse errors for valid JSON texts, or the resulting data
1203structure might not be queryable:
1204
1205One of the problems is that U+2028 and U+2029 are valid characters inside
1206JSON strings, but are not allowed in ECMAscript string literals, so the
1207following Perl fragment will not output something that can be guaranteed
1208to be parsable by javascript's C<eval>:
1209
1210 use JSON::XS;
1211
1212 print encode_json [chr 0x2028];
1213
1214The right fix for this is to use a proper JSON parser in your javascript
1215programs, and not rely on C<eval> (see for example Douglas Crockford's
1216F<json2.js> parser).
1217
1218If this is not an option, you can, as a stop-gap measure, simply encode to
1219ASCII-only JSON:
1220
1221 use JSON::XS;
1222
1223 print JSON::XS->new->ascii->encode ([chr 0x2028]);
1224
1225Note that this will enlarge the resulting JSON text quite a bit if you
1226have many non-ASCII characters. You might be tempted to run some regexes
1227to only escape U+2028 and U+2029, e.g.:
1228
1229 # DO NOT USE THIS!
1230 my $json = JSON::XS->new->utf8->encode ([chr 0x2028]);
1231 $json =~ s/\xe2\x80\xa8/\\u2028/g; # escape U+2028
1232 $json =~ s/\xe2\x80\xa9/\\u2029/g; # escape U+2029
1233 print $json;
1234
1235Note that I<this is a bad idea>: the above only works for U+2028 and
1236U+2029 and thus only for fully ECMAscript-compliant parsers. Many existing
1237javascript implementations, however, have issues with other characters as
1238well - using C<eval> naively simply I<will> cause problems.
1239
1240Another problem is that some javascript implementations reserve
1241some property names for their own purposes (which probably makes
1242them non-ECMAscript-compliant). For example, Iceweasel reserves the
1243C<__proto__> property name for it's own purposes.
1244
1245If that is a problem, you could parse try to filter the resulting JSON
1246output for these property strings, e.g.:
1247
1248 $json =~ s/"__proto__"\s*:/"__proto__renamed":/g;
1249
1250This works because C<__proto__> is not valid outside of strings, so every
1251occurence of C<"__proto__"\s*:> must be a string used as property name.
1252
1253If you know of other incompatibilities, please let me know.
1184 1254
1185 1255
1186=head2 JSON and YAML 1256=head2 JSON and YAML
1187 1257
1188You often hear that JSON is a subset of YAML. This is, however, a mass 1258You often hear that JSON is a subset of YAML. This is, however, a mass

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