Section: User Contributed Perl Documentation (3pm)
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JSON::Syck - JSON is YAML (but consider using JSON::XS instead!)
use JSON::Syck; # no exports by default
my $data = JSON::Syck::Load($json);
my $json = JSON::Syck::Dump($data);
# $file can be an IO object, or a filename
my $data = JSON::Syck::LoadFile($file);
# Dump into a pre-existing buffer
JSON::Syck is a syck implementation of JSON
parsing and generation. Because
syck gives you a fast and memory-efficient parser and dumper for JSON
However, a newer module JSON::XS, has since emerged. It is more flexible,
efficient and robust, so please consider using it instead of this module.
DIFFERENCE WITH JSON
You might want to know the difference between the JSON
Since JSON is a pure-perl module and JSON::Syck is based on libsyck,
JSON::Syck is supposed to be very fast and memory efficient. See
chansen's benchmark table at
JSON.pm comes with dozens of ways to do the same thing and lots of
options, while JSON::Syck doesn't. There's only "Load" and "Dump".
Oh, and JSON::Syck doesn't use camelCase method names :-)
For now, when you pass a scalar reference to JSON::Syck, it
dereferences to get the actual scalar value.
JSON::Syck raises an exception when you pass in circular references.
If you want to serialize self refernecing stuff, you should use
YAML which supports it.
When you pass subroutine reference, JSON::Syck dumps it as null.
By default this module doesn't touch any of utf-8 flags set in
strings, and assumes UTF-8
bytes to be passed and emit.
However, when you set $JSON::Syck::ImplicitUnicode to 1, this
module properly decodes UTF-8 binaries and sets UTF-8 flag everywhere,
JSON (UTF-8 bytes) => Perl (UTF-8 flagged)
JSON (UTF-8 flagged) => Perl (UTF-8 flagged)
Perl (UTF-8 bytes) => JSON (UTF-8 flagged)
Perl (UTF-8 flagged) => JSON (UTF-8 flagged)
By default, JSON::Syck::Dump will only transverse up to 512 levels of
a datastructure in order to avoid an infinite loop when it is
presented with an circular reference.
However, you set $JSON::Syck::MaxLevels to a larger value if you
have very complex structures.
Unfortunately, there's no implicit way to dump Perl UTF-8 flagged data
structure to utf-8 encoded JSON. To do this, simply use Encode module, e.g.:
use JSON::Syck qw(Dump);
my $json = encode_utf8( Dump($data) );
strings as in %uXXXX form.
use JSON::Syck qw(Dump);
According to the JSON
specification, all JSON
strings are to be double-quoted.
attributes, it may be more
convenient to use single quotes.
Set $JSON::Syck::SingleQuote to 1 will make both "Dump" and "Load" expect
single-quoted string literals.
Dumping into tied (or other magic variables) with "DumpInto"
might not work
properly in all cases.
When dumping with "DumpFile", some spacing might be wrong and
$JSON::Syck::SingleQuote might be handled incorrectly.
Audrey Tang <email@example.com
Tatsuhiko Miyagawa <firstname.lastname@example.org>
Copyright 2005-2009 by Audrey Tang <email@example.com
This software is released under the MIT license cited below.
The libsyck code bundled with this library is released by
``why the lucky stiff'', under a BSD-style license. See the COPYING
file for details.
The MIT License
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the ``Software''), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED ``AS IS'', WITHOUT WARRANTY OF ANY KIND, EXPRESS
OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
DEALINGS IN THE SOFTWARE.
- DIFFERENCE WITH JSON
- SCALAR REFERENCE
- SUBROUTINE REFERENCE
- UTF-8 FLAGS
- SEE ALSO
- The MIT License