Method: ALib::AbstractMain.optional_arguments

Defined in:

lib/alib-0.5.0/main.rb

.optional_arguments(*list) ⇒ Object

# File 'lib/alib-0.5.0/main.rb', line 265

def optional_arguments(*list)
#--{{{
  @optional_arguments ||= []
  list.flatten.each do |arg| 
    arg, default =
      case arg
        when Hash
          arg.to_a.first
        else
          [arg, nil]
      end
    @do_not_gc ||= [] 
    @do_not_gc << default unless @do_not_gc.include? default
    unless instance_methods.include? "#{ arg }"
      module_eval <<-code
        def #{ arg }(*__list)
          unless @#{ arg }
            @#{ arg } = ObjectSpace::_id2ref #{ default.object_id }
          end
          if __list.empty?
            @#{ arg }
          else
            send('#{ arg }=', *__list)
          end
        end
        def #{ arg }=(__arg, *__list)
          if __list.empty?
            @#{ arg } = __arg
          else
            @#{ arg } = ([__arg] + __list)
          end
        end
        def #{ arg }?
          defined? @#{ arg } and @#{ arg }
        end
      code
    end
    @optional_arguments << "#{ arg }"
  end
  @optional_arguments
#--}}}
end