pathex.expressions.nary_operators.union module

class Union(*args)

Bases: pathex.expressions.nary_operators.nary_operator.NAryOperator

This class represents a union of languages.

A union of languages is equivalent to the union of the sets.

>>> from pathex.expressions.aliases import *
>>> exp = U('abcd')
>>> assert exp.get_language() == exp.get_generator().get_language() == {'a', 'b', 'c', 'd'}

A union may also be constructed by using the | operator.

>>> exp = U('ab') | U('cd')
>>> assert exp.get_language() == exp.get_generator().get_language() == {'a', 'b', 'c', 'd'}

>>> exp = C('ab') | C('cd')
>>> assert exp.get_language() == exp.get_generator().get_language() == {'ab', 'cd'}

>>> exp = 'a' | ( 'b' + U('cd') )
>>> assert exp.get_language() == exp.get_generator().get_language() == {'a', 'bc', 'bd'}

arguments: Collection