module Regexp::Expression::Shared

exp.is? :dot, [:meta, :escape]
# is it a :meta or :escape :dot

exp.is? :dot, :meta
# is it a :meta :dot

exp.is? :character, :set
# is it a :character and a :set

exp.is? :capture
# is it a :capture

exp.is? :* # always returns true
# Any expressions

test_type.
Test if this expression has the given test_token, and optionally a given

def is?(test_token, test_type = nil)
  return true if test_token === :*
  token == test_token and (test_type ? type?(test_type) : true)
end