You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: regexp.rb
    path of file: ./repos/mutant/lib/mutant/mutator
    
    the code of the file until where you have to start completion: # frozen_string_literal: true

module Mutant
  class Mutator
    class Regexp < self
      def 
    
        def dispatch
          return if input.name.start_with?('_') || subexpressions.empty?

          emit_passive_group

          emit_expression(
            klass: ::Regexp::Expression::Group::Named,
            text:  "(?<_#{input.name}>"
          )
        end