class Regexp::Expression::Subexpression

def to_s(format = :full)
  # Note: the format does not get passed down to subexpressions.
  # Note: cant use #text accessor, b/c it is overriden as def text; to_s end
  # in Expression::Sequence, causing infinite recursion. Clean-up needed.
  "#{@text}#{expressions.join}#{quantifier_affix(format)}"
end