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require 'psych/psych'
require 'psych/visitable'
require 'psych/nodes'
require 'psych/visitors'
require 'psych/handler'
require 'psych/tree_builder'
require 'psych/parser'
require 'psych/omap'
require 'psych/set'
###
# = Overview
#
# Psych is a YAML parser and emitter. Psych leverages
# libyaml[http://libyaml.org] for it's 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.
#
# = I NEED TO PARSE OR EMIT YAML RIGHT NOW!
#
# # Parse some YAML
# Psych.load("--- foo") # => "foo"
#
# # Emit some YAML
# Psych.dump("foo") # => "--- foo\n...\n"
# { :a => 'b'}.to_yaml # => "---\n:a: b\n"
#
# Got more time on your hands? Keep on reading!
#
# == YAML Parsing
#
# Psych provides a range of interfaces for parsing a YAML document ranging from
# low level to high level, depending on your parsing needs. At the lowest
# level, is an event based parser. Mid level is access to the raw YAML AST,
# and at the highest level is the ability to unmarshal YAML to ruby objects.
#
# === Low level parsing
#
# The lowest level parser should be used when the YAML input is already known,
# and the developer does not want to pay the price of building an AST or
# automatic detection and conversion to ruby objects. See Psych::Parser for
# more information on using the event based parser.
#
# === Mid level parsing
#
# Psych provides access to an AST produced from parsing a YAML document. This
# tree is built using the Psych::Parser and Psych::TreeBuilder. The AST can
# be examined and manipulated freely. Please see Psych::yaml_ast,
# Psych::Nodes, and Psych::Nodes::Node for more information on dealing with
# YAML syntax trees.
#
# === High level parsing
#
# The high level YAML parser provided by Psych simply takes YAML as input and
# returns a Ruby data structure. For information on using the high level parser
# see Psych.load
#
# == YAML Emitting
#
# Psych provides a range of interfaces ranging from low to high level for
# producing YAML documents. Very similar to the YAML parsing interfaces, Psych
# provides at the lowest level, an event based system, mid-level is building
# a YAML AST, and the highest level is converting a Ruby object straight to
# a YAML document.
#
# === Low level emitting
#
# The lowest level emitter is an event based system. Events are sent to a
# Psych::Emitter object. That object knows how to convert the events to a YAML
# document. This interface should be used when document format is known in
# advance or speed is a concern. See Psych::Emitter for more information.
#
# === Mid level emitting
#
# At the mid level is building an AST. This AST is exactly the same as the AST
# used when parsing a YAML document. Users can build an AST by hand and the
# AST knows how to emit itself as a YAML document. See Psych::Nodes,
# Psych::Nodes::Node, and Psych::TreeBuilder for more information on building
# a YAML AST.
#
# === High level emitting
#
# The high level emitter has the easiest interface. Psych simply takes a Ruby
# data structure and converts it to a YAML document. See Psych.dump for more
# information on dumping a Ruby data structure.
module Psych
# The version is Psych you're using
VERSION = '1.0.0'
# The version of libyaml Psych is using
LIBYAML_VERSION = Psych.libyaml_version.join '.'
###
# Load +yaml+ in to a Ruby data structure. If multiple documents are
# provided, the object contained in the first document will be returned.
#
# Example:
#
# Psych.load("--- a") # => 'a'
# Psych.load("---\n - a\n - b") # => ['a', 'b']
def self.load yaml
parse(yaml).to_ruby
end
###
# Parse a YAML string in +yaml+. Returns the first object of a YAML AST.
#
# Example:
#
# Psych.load("---\n - a\n - b") # => #<Psych::Nodes::Sequence:0x00>
#
# See Psych::Nodes for more information about YAML AST.
def self.parse yaml
yaml_ast(yaml).children.first.children.first
end
###
# Parse a YAML string in +yaml+. Returns the full AST for the YAML document.
# This method can handle multiple YAML documents contained in +yaml+.
#
# Example:
#
# Psych.load("---\n - a\n - b") # => #<Psych::Nodes::Stream:0x00>
#
# See Psych::Nodes for more information about YAML AST.
def self.yaml_ast yaml
parser = Psych::Parser.new(TreeBuilder.new)
parser.parse yaml
parser.handler.root
end
###
# Dump Ruby object +o+ to a YAML string using +options+.
#
# Example:
#
# Psych.dump(['a', 'b']) # => "---\n- a\n- b\n"
def self.dump o, options = {}
visitor = Psych::Visitors::YAMLTree.new options
visitor.accept o
visitor.tree.to_yaml
end
###
# Load multiple documents given in +yaml+, yielding each document to
# the block provided.
def self.load_documents yaml, &block
yaml_ast(yaml).children.each do |child|
block.call child.to_ruby
end
end
# :stopdoc:
@domain_types = {}
def self.add_domain_type domain, type_tag, &block
@domain_types[type_tag] = [domain, block]
end
class << self; attr_accessor :domain_types; end
# :startdoc:
end
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