class Regexp::Expression::Group::Base

def to_s(format = :full)
  s = ''
  case format
  when :base
    s << @text.dup
    s << @expressions.join
    s << ')'
  else
    s << @text.dup
    s << @expressions.join
    s << ')'
    s << @quantifier.to_s if quantified?
  end
  s
end