YAML::Syck - phpMan

YAML::Syck(3) User Contributed Perl Documentation YAML::Syck(3)

NAME
YAML::Syck - Fast, lightweight YAML loader and dumper

SYNOPSIS
use YAML::Syck;

# Set this for interoperability with other YAML/Syck bindings:
# e.g. Load('Yes') becomes 1 and Load('No') becomes ''.
$YAML::Syck::ImplicitTyping = 1;

$data = Load($yaml);
$yaml = Dump($data);

# $file can be an IO object, or a filename
$data = LoadFile($file);
DumpFile($file, $data);

# A string with multiple YAML streams in it
$yaml = Dump(@data);
@data = Load($yaml);

# Dumping into a pre-existing output buffer
my $yaml;
DumpInto(\$yaml, @data);

DESCRIPTION
This module provides a Perl interface to the libsyck data serialization library. It
exports the "Dump" and "Load" functions for converting Perl data structures to YAML
strings, and the other way around.

NOTE: If you are working with other language's YAML/Syck bindings (such as Ruby), please
set $YAML::Syck::ImplicitTyping to 1 before calling the "Load"/"Dump" functions. The
default setting is for preserving backward-compatibility with "YAML.pm".

Differences Between YAML::Syck and YAML
Error handling
Some calls are designed to die rather than returning YAML. You should wrap your calls in
eval to assure you do not get unexpected results.

FLAGS
$YAML::Syck::Headless
Defaults to false. Setting this to a true value will make "Dump" omit the leading "---\n"
marker.

$YAML::Syck::SortKeys
Defaults to false. Setting this to a true value will make "Dump" sort hash keys.

$YAML::Syck::SingleQuote
Defaults to false. Setting this to a true value will make "Dump" always emit single
quotes instead of bare strings.

$YAML::Syck::ImplicitTyping
Defaults to false. Setting this to a true value will make "Load" recognize various
implicit types in YAML, such as unquoted "true", "false", as well as integers and
floating-point numbers. Otherwise, only "~" is recognized to be "undef".

$YAML::Syck::ImplicitUnicode
Defaults to false. For Perl 5.8.0 or later, setting this to a true value will make "Load"
set Unicode flag on for every string that contains valid UTF8 sequences, and make "Dump"
return a unicode string.

Regardless of this flag, Unicode strings are dumped verbatim without escaping; byte
strings with high-bit set will be dumped with backslash escaping.

However, because YAML does not distinguish between these two kinds of strings, so this
flag will affect loading of both variants of strings.

If you want to use LoadFile or DumpFile with unicode, you are required to open your own
file in order to assure it's UTF8 encoded:

open(my $fh, ">:encoding(UTF-8)", "out.yml");
DumpFile($fh, $hashref);

$YAML::Syck::ImplicitBinary
Defaults to false. For Perl 5.8.0 or later, setting this to a true value will make "Dump"
generate Base64-encoded "!!binary" data for all non-Unicode scalars containing high-bit
bytes.

$YAML::Syck::UseCode / $YAML::Syck::LoadCode / $YAML::Syck::DumpCode
These flags control whether or not to try and eval/deparse perl source code; each of them
defaults to false.

Setting $YAML::Syck::UseCode to a true value is equivalent to setting both
$YAML::Syck::LoadCode and $YAML::Syck::DumpCode to true.

$YAML::Syck::LoadBlessed
Defaults to true. Setting to false will block YAML::Syck from doing ANY blessing. This is
an interface change since 1.21. The variable name was misleading, implying that no
blessing would happen when in fact it did.

Prior to 1.22, setting this to a false value only prevented "Load" from blessing tag names
that did not begin with "!!perl" or "!perl";.

BUGS
Dumping Glob/IO values do not work yet.

Dumping of Tied variables is unsupported.

Dumping into tied (or other magic variables) with "DumpInto" might not work properly in
all cases.

CAVEATS
This module implements the YAML 1.0 spec. To deal with data in YAML 1.1, please use the
"YAML::XS" module instead.

The current implementation bundles libsyck source code; if your system has a site-wide
shared libsyck, it will not be used.

Tag names such as "!!perl/hash:Foo" is blessed into the package "Foo", but the "!hs/foo"
and "!!hs/Foo" tags are blessed into "hs::Foo". Note that this holds true even if the tag
contains non-word characters; for example, "!haskell.org/Foo" is blessed into
"haskell.org::Foo". Please use Class::Rebless to cast it into other user-defined
packages. You can also set the LoadBlessed flag false to disable all blessing.

This module has a lot of known issues
<https://rt.cpan.org/Public/Dist/Display.html?Name=YAML-Syck> and has only been semi-
actively maintained since 2007. If you encounter an issue with it probably won't be fixed
unless you offer up a patch <http://github.com/toddr/YAML-Syck> in Git that's ready for
release.

There are still good reasons to use this module, such as better interoperability with
other syck wrappers (like Ruby's), or some edge case of YAML's syntax that it handles
better. It'll probably work perfectly for you, but if it doesn't you may want to look at
YAML::XS, or perhaps at looking another serialization format like JSON.