extract (Templater::ArgumentDescription)

    # File lib/templater/description.rb, line 45
        def extract(argument)
          case options[:as]
          when :hash
            if argument.is_a?(String)
              return argument.split(',').inject({}) do |h, pair|
                key, value = pair.strip.split(':')
                raise Templater::MalformattedArgumentError, "Expected '#{argument.inspect}' to be a key/value pair" unless key and value
                h[key] = value
                h
              end
            end
          when :array
            return argument.split(',') if argument.is_a?(String)
          end
          return argument
        end