class Regexp::Scanner

def emit_meta_control_sequence(data, ts, te, token)

def emit_meta_control_sequence(data, ts, te, token)
  if data.last < 0x00 || data.last > 0x7F
    validation_error(:sequence, 'escape', token.to_s)
  end
  emit(:escape, token, copy(data, ts-1, te))
end