# File lib/cucumber/rb_support/rb_step_definition.rb, line 27
      def initialize(rb_language, regexp, proc)
        raise MissingProc if proc.nil?
        if String === regexp
          p = Regexp.escape(regexp)
          p = p.gsub(/\\\$\w+/, '(.*)') # Replace $var with (.*)
          regexp = Regexp.new("^#{p}$") 
        end
        @rb_language, @regexp, @proc = rb_language, regexp, proc
        @rb_language.available_step_definition(regexp_source, file_colon_line)
      end