JezK
Edit File: tag.rb
# -*- mode: ruby; ruby-indent-level: 4; tab-width: 4 -*- vim: sw=4 ts=4 # $Id: tag.rb 16084 2008-04-19 11:45:39Z knu $ # # = yaml/tag.rb: methods for associating a taguri to a class. # # Author:: why the lucky stiff # module YAML # A dictionary of taguris which map to # Ruby classes. @@tagged_classes = {} # # Associates a taguri _tag_ with a Ruby class _cls_. The taguri is used to give types # to classes when loading YAML. Taguris are of the form: # # tag:authorityName,date:specific # # The +authorityName+ is a domain name or email address. The +date+ is the date the type # was issued in YYYY or YYYY-MM or YYYY-MM-DD format. The +specific+ is a name for # the type being added. # # For example, built-in YAML types have 'yaml.org' as the +authorityName+ and '2002' as the # +date+. The +specific+ is simply the name of the type: # # tag:yaml.org,2002:int # tag:yaml.org,2002:float # tag:yaml.org,2002:timestamp # # The domain must be owned by you on the +date+ declared. If you don't own any domains on the # date you declare the type, you can simply use an e-mail address. # # tag:why@ruby-lang.org,2004:notes/personal # def YAML.tag_class( tag, cls ) if @@tagged_classes.has_key? tag warn "class #{ @@tagged_classes[tag] } held ownership of the #{ tag } tag" end @@tagged_classes[tag] = cls end # Returns the complete dictionary of taguris, paired with classes. The key for # the dictionary is the full taguri. The value for each key is the class constant # associated to that taguri. # # YAML.tagged_classes["tag:yaml.org,2002:int"] => Integer # def YAML.tagged_classes @@tagged_classes end end class Module # :stopdoc: # Adds a taguri _tag_ to a class, used when dumping or loading the class # in YAML. See YAML::tag_class for detailed information on typing and # taguris. def yaml_as( tag, sc = true ) verbose, $VERBOSE = $VERBOSE, nil class_eval <<-"end;", __FILE__, __LINE__+1 attr_writer :taguri def taguri if respond_to? :to_yaml_type YAML::tagurize( to_yaml_type[1..-1] ) else return @taguri if defined?(@taguri) and @taguri tag = #{ tag.dump } if self.class.yaml_tag_subclasses? and self.class != YAML::tagged_classes[tag] tag = "\#{ tag }:\#{ self.class.yaml_tag_class_name }" end tag end end def self.yaml_tag_subclasses?; #{ sc ? 'true' : 'false' }; end end; YAML::tag_class tag, self ensure $VERBOSE = verbose end # Transforms the subclass name into a name suitable for display # in a subclassed tag. def yaml_tag_class_name self.name end # Transforms the subclass name found in the tag into a Ruby # constant name. def yaml_tag_read_class( name ) name end end