Psych is a YAML parser and emitter. Psych leverages libyaml for its YAML parsing and emitting capabilities. In addition to wrapping libyaml, Psych also knows how to serialize and de-serialize most Ruby objects to and from the YAML format.
# Safely load YAML in to a Ruby object
Psych.safe_load('--- foo') # => 'foo'
# Emit YAML from a Ruby object
Psych.dump("foo") # => "--- foo\n...\n"- libyaml
Psych has been included with MRI since 1.9.2, and is the default YAML parser in 1.9.3.
If you want a newer gem release of Psych, you can use rubygems:
gem install psych
In order to use the gem release in your app, and not the stdlib version, you'll need the following:
gem 'psych'
require 'psych'
Or if you use Bundler add this to your Gemfile:
gem 'psych'
JRuby ships with a pure Java implementation of Psych.
If you're on Rubinius, Psych is available in 1.9 mode, please refer to the Language Modes section of the Rubinius README for more information on building and 1.9 mode.
Copyright 2009 Aaron Patterson, et al.
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