def const(name, format = nil, cast = '', ruby_name = nil, converter = nil,
              &converter_proc)
      format ||= '%d'
      cast ||= ''

      if converter_proc and converter then
        raise ArgumentError, "Supply only converter or converter block"
      end

      converter = converter_proc if converter.nil?

      const = Constant.new name, format, cast, ruby_name, converter
      @constants[name.to_s] = const
      return const
    end
def const(name, format = nil, cast = '', ruby_name = nil, converter = nil,
              &converter_proc)
      format ||= '%d'
      cast ||= ''

      if converter_proc and converter then
        raise ArgumentError, "Supply only converter or converter block"
      end

      converter = converter_proc if converter.nil?

      const = Constant.new name, format, cast, ruby_name, converter
      @constants[name.to_s] = const
      return const
    end
Request the value for C constant +name+.  +format+ is a printf format
 string to print the value out, and +cast+ is a C cast for the value.
 +ruby_name+ allows you to give the constant an alternate ruby name for
 #to_ruby.  +converter+ or +converter_proc+ allow you to convert the
 value from a string to the appropriate type for #to_ruby.