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Comparing JSON-XS/XS.pm (file contents):
Revision 1.133 by root, Tue Aug 17 23:27:36 2010 UTC vs.
Revision 1.139 by root, Thu May 23 09:31:32 2013 UTC

101 101
102package JSON::XS; 102package JSON::XS;
103 103
104use common::sense; 104use common::sense;
105 105
106our $VERSION = '2.3'; 106our $VERSION = 2.34;
107our @ISA = qw(Exporter); 107our @ISA = qw(Exporter);
108 108
109our @EXPORT = qw(encode_json decode_json to_json from_json); 109our @EXPORT = qw(encode_json decode_json to_json from_json);
110 110
111sub to_json($) { 111sub to_json($) {
432If C<$enable> is true (or missing), then the C<encode> method will output JSON objects 432If C<$enable> is true (or missing), then the C<encode> method will output JSON objects
433by sorting their keys. This is adding a comparatively high overhead. 433by sorting their keys. This is adding a comparatively high overhead.
434 434
435If C<$enable> is false, then the C<encode> method will output key-value 435If C<$enable> is false, then the C<encode> method will output key-value
436pairs in the order Perl stores them (which will likely change between runs 436pairs in the order Perl stores them (which will likely change between runs
437of the same script). 437of the same script, and can change even within the same run from 5.18
438onwards).
438 439
439This option is useful if you want the same data structure to be encoded as 440This option is useful if you want the same data structure to be encoded as
440the same JSON text (given the same overall settings). If it is disabled, 441the same JSON text (given the same overall settings). If it is disabled,
441the same hash might be encoded differently even if contains the same data, 442the same hash might be encoded differently even if contains the same data,
442as key-value pairs have no inherent ordering in Perl. 443as key-value pairs have no inherent ordering in Perl.
713calls). 714calls).
714 715
715JSON::XS will only attempt to parse the JSON text once it is sure it 716JSON::XS will only attempt to parse the JSON text once it is sure it
716has enough text to get a decisive result, using a very simple but 717has enough text to get a decisive result, using a very simple but
717truly incremental parser. This means that it sometimes won't stop as 718truly incremental parser. This means that it sometimes won't stop as
718early as the full parser, for example, it doesn't detect parenthese 719early as the full parser, for example, it doesn't detect mismatched
719mismatches. The only thing it guarantees is that it starts decoding as 720parentheses. The only thing it guarantees is that it starts decoding as
720soon as a syntactically valid JSON text has been seen. This means you need 721soon as a syntactically valid JSON text has been seen. This means you need
721to set resource limits (e.g. C<max_size>) to ensure the parser will stop 722to set resource limits (e.g. C<max_size>) to ensure the parser will stop
722parsing in the presence if syntax errors. 723parsing in the presence if syntax errors.
723 724
724The following methods implement this incremental parser. 725The following methods implement this incremental parser.
1255well - using C<eval> naively simply I<will> cause problems. 1256well - using C<eval> naively simply I<will> cause problems.
1256 1257
1257Another problem is that some javascript implementations reserve 1258Another problem is that some javascript implementations reserve
1258some property names for their own purposes (which probably makes 1259some property names for their own purposes (which probably makes
1259them non-ECMAscript-compliant). For example, Iceweasel reserves the 1260them non-ECMAscript-compliant). For example, Iceweasel reserves the
1260C<__proto__> property name for it's own purposes. 1261C<__proto__> property name for its own purposes.
1261 1262
1262If that is a problem, you could parse try to filter the resulting JSON 1263If that is a problem, you could parse try to filter the resulting JSON
1263output for these property strings, e.g.: 1264output for these property strings, e.g.:
1264 1265
1265 $json =~ s/"__proto__"\s*:/"__proto__renamed":/g; 1266 $json =~ s/"__proto__"\s*:/"__proto__renamed":/g;
1319that difficult or long) and finally make YAML compatible to it, and 1320that difficult or long) and finally make YAML compatible to it, and
1320educating users about the changes, instead of spreading lies about the 1321educating users about the changes, instead of spreading lies about the
1321real compatibility for many I<years> and trying to silence people who 1322real compatibility for many I<years> and trying to silence people who
1322point out that it isn't true. 1323point out that it isn't true.
1323 1324
1324Addendum/2009: the YAML 1.2 spec is still incomaptible with JSON, even 1325Addendum/2009: the YAML 1.2 spec is still incompatible with JSON, even
1325though the incompatibilities have been documented (and are known to 1326though the incompatibilities have been documented (and are known to Brian)
1326Brian) for many years and the spec makes explicit claims that YAML is a 1327for many years and the spec makes explicit claims that YAML is a superset
1327superset of JSON. It would be so easy to fix, but apparently, bullying and 1328of JSON. It would be so easy to fix, but apparently, bullying people and
1328corrupting userdata is so much easier. 1329corrupting userdata is so much easier.
1329 1330
1330=back 1331=back
1331 1332
1332 1333
1445process simulations - use fork, it's I<much> faster, cheaper, better). 1446process simulations - use fork, it's I<much> faster, cheaper, better).
1446 1447
1447(It might actually work, but you have been warned). 1448(It might actually work, but you have been warned).
1448 1449
1449 1450
1451=head1 THE PERILS OF SETLOCALE
1452
1453Sometimes people avoid the Perl locale support and directly call the
1454system's setlocale function with C<LC_ALL>.
1455
1456This breaks both perl and modules such as JSON::XS, as stringification of
1457numbers no longer works correcly (e.g. C<$x = 0.1; print "$x"+1> might
1458print C<1>, and JSON::XS might output illegal JSON as JSON::XS relies on
1459perl to stringify numbers).
1460
1461The solution is simple: don't call C<setlocale>, or use it for only those
1462categories you need, such as C<LC_MESSAGES> or C<LC_CTYPE>.
1463
1464If you need C<LC_NUMERIC>, you should enable it only around the code that
1465actually needs it (avoiding stringification of numbers), and restore it
1466afterwards.
1467
1468
1450=head1 BUGS 1469=head1 BUGS
1451 1470
1452While the goal of this module is to be correct, that unfortunately does 1471While the goal of this module is to be correct, that unfortunately does
1453not mean it's bug-free, only that I think its design is bug-free. If you 1472not mean it's bug-free, only that I think its design is bug-free. If you
1454keep reporting bugs they will be fixed swiftly, though. 1473keep reporting bugs they will be fixed swiftly, though.

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