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
Psych supported the static build with specific version of libyaml sources. You can build psych with libyaml-0.2.5 like this.
gem install psych -- --with-libyaml-source-dir=/path/to/libyaml-0.2.5
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.
Copyright 2009 Aaron Patterson, et al.
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