1YAML::Syck(3) User Contributed Perl Documentation YAML::Syck(3)
2
6 YAML::Syck - Fast, lightweight YAML loader and dumper
7
9 use YAML::Syck;
10 # Set this for interoperability with other YAML/Syck bindings:
12 # e.g. Load('Yes') becomes 1 and Load('No') becomes ''.
13 $YAML::Syck::ImplicitTyping = 1;
14 $data = Load($yaml);
16 $yaml = Dump($data);
17 # $file can be an IO object, or a filename
19 $data = LoadFile($file);
20 DumpFile($file, $data);
21 # A string with multiple YAML streams in it
23 $yaml = Dump(@data);
24 @data = Load($yaml);
25 # Dumping into a pre-existing output buffer
27 my $yaml;
28 DumpInto(\$yaml, @data);
29
31 This module provides a Perl interface to the libsyck data serialization
32 library. It exports the "Dump" and "Load" functions for converting
33 Perl data structures to YAML strings, and the other way around.
34 NOTE: If you are working with other language's YAML/Syck bindings (such
36 as Ruby), please set $YAML::Syck::ImplicitTyping to 1 before calling
37 the "Load"/"Dump" functions. The default setting is for preserving
38 backward-compatibility with "YAML.pm".
39
41 Error handling
42 Some calls are designed to die rather than returning YAML. You should
43 wrap your calls in eval to assure you do not get unexpected results.
44
46 $YAML::Syck::Headless
47 Defaults to false. Setting this to a true value will make "Dump" omit
48 the leading "---\n" marker.
49 $YAML::Syck::SortKeys
51 Defaults to false. Setting this to a true value will make "Dump" sort
52 hash keys.
53 $YAML::Syck::SingleQuote
55 Defaults to false. Setting this to a true value will make "Dump"
56 always emit single quotes instead of bare strings.
57 $YAML::Syck::ImplicitTyping
59 Defaults to false. Setting this to a true value will make "Load"
60 recognize various implicit types in YAML, such as unquoted "true",
61 "false", as well as integers and floating-point numbers. Otherwise,
62 only "~" is recognized to be "undef".
63 $YAML::Syck::ImplicitUnicode
65 Defaults to false. For Perl 5.8.0 or later, setting this to a true
66 value will make "Load" set Unicode flag on for every string that
67 contains valid UTF8 sequences, and make "Dump" return a unicode string.
68 Regardless of this flag, Unicode strings are dumped verbatim without
70 escaping; byte strings with high-bit set will be dumped with backslash
71 escaping.
72 However, because YAML does not distinguish between these two kinds of
74 strings, so this flag will affect loading of both variants of strings.
75 If you want to use LoadFile or DumpFile with unicode, you are required
77 to open your own file in order to assure it's UTF8 encoded:
78 open(my $fh, ">:encoding(UTF-8)", "out.yml");
80 DumpFile($fh, $hashref);
81 $YAML::Syck::ImplicitBinary
83 Defaults to false. For Perl 5.8.0 or later, setting this to a true
84 value will make "Dump" generate Base64-encoded "!!binary" data for all
85 non-Unicode scalars containing high-bit bytes.
86 $YAML::Syck::UseCode / $YAML::Syck::LoadCode / $YAML::Syck::DumpCode
88 These flags control whether or not to try and eval/deparse perl source
89 code; each of them defaults to false.
90 Setting $YAML::Syck::UseCode to a true value is equivalent to setting
92 both $YAML::Syck::LoadCode and $YAML::Syck::DumpCode to true.
93 $YAML::Syck::LoadBlessed
95 Defaults to true. Setting to false will block YAML::Syck from doing ANY
96 blessing. This is an interface change since 1.21. The variable name was
97 misleading, implying that no blessing would happen when in fact it did.
98 Prior to 1.22, setting this to a false value only prevented "Load" from
100 blessing tag names that did not begin with "!!perl" or "!perl";.
101
103 Dumping Glob/IO values do not work yet.
104 Dumping of Tied variables is unsupported.
106 Dumping into tied (or other magic variables) with "DumpInto" might not
108 work properly in all cases.
109
111 This module implements the YAML 1.0 spec. To deal with data in YAML
112 1.1, please use the "YAML::XS" module instead.
113 The current implementation bundles libsyck source code; if your system
115 has a site-wide shared libsyck, it will not be used.
116 Tag names such as "!!perl/hash:Foo" is blessed into the package "Foo",
118 but the "!hs/foo" and "!!hs/Foo" tags are blessed into "hs::Foo". Note
119 that this holds true even if the tag contains non-word characters; for
120 example, "!haskell.org/Foo" is blessed into "haskell.org::Foo". Please
121 use Class::Rebless to cast it into other user-defined packages. You can
122 also set the LoadBlessed flag false to disable all blessing.
123 This module has a lot of known issues
125 <https://rt.cpan.org/Public/Dist/Display.html?Name=YAML-Syck> and has
126 only been semi-actively maintained since 2007. If you encounter an
127 issue with it probably won't be fixed unless you offer up a patch
128 <http://github.com/toddr/YAML-Syck> in Git that's ready for release.
129 There are still good reasons to use this module, such as better
131 interoperability with other syck wrappers (like Ruby's), or some edge
132 case of YAML's syntax that it handles better. It'll probably work
133 perfectly for you, but if it doesn't you may want to look at YAML::XS,
134 or perhaps at looking another serialization format like JSON.
135
137 YAML, JSON::Syck
138 <http://www.yaml.org/>
140
142 Audrey Tang <cpan@audreyt.org>
143
145 Copyright 2005-2009 by Audrey Tang <cpan@audreyt.org>.
146 This software is released under the MIT license cited below.
148 The libsyck code bundled with this library is released by "why the
150 lucky stiff", under a BSD-style license. See the COPYING file for
151 details.
152 The "MIT" License
154 Permission is hereby granted, free of charge, to any person obtaining a
155 copy of this software and associated documentation files (the
156 "Software"), to deal in the Software without restriction, including
157 without limitation the rights to use, copy, modify, merge, publish,
158 distribute, sublicense, and/or sell copies of the Software, and to
159 permit persons to whom the Software is furnished to do so, subject to
160 the following conditions:
161 The above copyright notice and this permission notice shall be included
163 in all copies or substantial portions of the Software.
164 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
166 OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
167 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
168 IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
169 CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
170 TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
171 SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
172perl v5.28.0 2017-04-20 YAML::Syck(3)