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Comparing JSON-XS/XS.pm (file contents):
Revision 1.48 by root, Mon Jun 25 22:11:39 2007 UTC vs.
Revision 1.54 by root, Tue Jul 10 16:22:31 2007 UTC

… …
9 # exported functions, they croak on error 9 # exported functions, they croak on error
10 # and expect/generate UTF-8 10 # and expect/generate UTF-8
11 11
12 $utf8_encoded_json_text = to_json $perl_hash_or_arrayref; 12 $utf8_encoded_json_text = to_json $perl_hash_or_arrayref;
13 $perl_hash_or_arrayref = from_json $utf8_encoded_json_text; 13 $perl_hash_or_arrayref = from_json $utf8_encoded_json_text;
14
15 # objToJson and jsonToObj aliases to to_json and from_json
16 # are exported for compatibility to the JSON module,
17 # but should not be used in new code.
18 14
19 # OO-interface 15 # OO-interface
20 16
21 $coder = JSON::XS->new->ascii->pretty->allow_nonref; 17 $coder = JSON::XS->new->ascii->pretty->allow_nonref;
22 $pretty_printed_unencoded = $coder->encode ($perl_scalar); 18 $pretty_printed_unencoded = $coder->encode ($perl_scalar);
… …
85 81
86package JSON::XS; 82package JSON::XS;
87 83
88use strict; 84use strict;
89 85
90our $VERSION = '1.4'; 86our $VERSION = '1.41';
91our @ISA = qw(Exporter); 87our @ISA = qw(Exporter);
92 88
93our @EXPORT = qw(to_json from_json objToJson jsonToObj); 89our @EXPORT = qw(to_json from_json);
94 90
95use Exporter; 91use Exporter;
96use XSLoader; 92use XSLoader;
97 93
98=head1 FUNCTIONAL INTERFACE 94=head1 FUNCTIONAL INTERFACE
… …
351future, global hooks might get installed that influence C<decode> and are 347future, global hooks might get installed that influence C<decode> and are
352enabled by this setting. 348enabled by this setting.
353 349
354If C<$enable> is false, then the C<allow_blessed> setting will decide what 350If C<$enable> is false, then the C<allow_blessed> setting will decide what
355to do when a blessed object is found. 351to do when a blessed object is found.
352
353=item $json = $json->filter_json_object ([$coderef->($hashref)])
354
355When C<$coderef> is specified, it will be called from C<decode> each
356time it decodes a JSON object. The only argument is a reference to the
357newly-created hash. If the code references returns a single scalar (which
358need not be a reference), this value (i.e. a copy of that scalar to avoid
359aliasing) is inserted into the deserialised data structure. If it returns
360an empty list (NOTE: I<not> C<undef>, which is a valid scalar), the
361original deserialised hash will be inserted. This setting can slow down
362decoding considerably.
363
364When C<$coderef> is omitted or undefined, any existing callback will
365be removed and C<decode> will not change the deserialised hash in any
366way.
367
368Example, convert all JSON objects into the integer 5:
369
370 my $js = JSON::XS->new->filter_json_object (sub { 5 });
371 # returns [5]
372 $js->decode ('[{}]')
373 # throw an exception because allow_nonref is not enabled
374 # so a lone 5 is not allowed.
375 $js->decode ('{"a":1, "b":2}');
376
377=item $json = $json->filter_json_single_key_object ($key [=> $coderef->($value)])
378
379Works remotely similar to C<filter_json_object>, but is only called for
380JSON objects having a single key named C<$key>.
381
382This C<$coderef> is called before the one specified via
383C<filter_json_object>, if any. It gets passed the single value in the JSON
384object. If it returns a single value, it will be inserted into the data
385structure. If it returns nothing (not even C<undef> but the empty list),
386the callback from C<filter_json_object> will be called next, as if no
387single-key callback were specified.
388
389If C<$coderef> is omitted or undefined, the corresponding callback will be
390disabled. There can only ever be one callback for a given key.
391
392As this callback gets called less often then the C<filter_json_object>
393one, decoding speed will not usually suffer as much. Therefore, single-key
394objects make excellent targets to serialise Perl objects into, especially
395as single-key JSON objects are as close to the type-tagged value concept
396as JSON gets (its basically an ID/VALUE tuple). Of course, JSON does not
397support this in any way, so you need to make sure your data never looks
398like a serialised Perl hash.
399
400Typical names for the single object key are C<__class_whatever__>, or
401C<$__dollars_are_rarely_used__$> or C<}ugly_brace_placement>, or even
402things like C<__class_md5sum(classname)__>, to reduce the risk of clashing
403with real hashes.
404
405Example, decode JSON objects of the form C<< { "__widget__" => <id> } >>
406into the corresponding C<< $WIDGET{<id>} >> object:
407
408 # return whatever is in $WIDGET{5}:
409 JSON::XS
410 ->new
411 ->filter_json_single_key_object (__widget__ => sub {
412 $WIDGET{ $_[0] }
413 })
414 ->decode ('{"__widget__": 5')
415
416 # this can be used with a TO_JSON method in some "widget" class
417 # for serialisation to json:
418 sub WidgetBase::TO_JSON {
419 my ($self) = @_;
420
421 unless ($self->{id}) {
422 $self->{id} = ..get..some..id..;
423 $WIDGET{$self->{id}} = $self;
424 }
425
426 { __widget__ => $self->{id} }
427 }
356 428
357=item $json = $json->shrink ([$enable]) 429=item $json = $json->shrink ([$enable])
358 430
359Perl usually over-allocates memory a bit when allocating space for 431Perl usually over-allocates memory a bit when allocating space for
360strings. This flag optionally resizes strings generated by either 432strings. This flag optionally resizes strings generated by either

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