def unary_checks(Q, operation):
Q_plus = beautifier.do(repeat.do(Q))
Q_star = beautifier.do(repeat.do(Q, min_repetition_n=0))
Q_is_Q_star = identity.do(Q, Q_star)
Q_is_Q_plus = identity.do(Q, Q_plus)
# \Cut{Q Q} = \Nothing
y = operation(Q, Q)
assert y.is_Nothing()
# if Q != Q+: \CutBegin{Q+ Q} = Q*
if not Q_is_Q_plus:
y = operation(Q_plus, Q)
assert identity.do(y, Q_star)
# if Q != Q*: \CutBegin{Q* Q} = Q*
if not Q_is_Q_star:
y = operation(Q_star, Q)
assert identity.do(y, Q_star)
# \Cut{Q \Nothing} = Q
y = operation(Q, DFA.Nothing())
assert identity.do(y, Q)
# \Cut{\Nothing Q} = \Nothing
y = operation(DFA.Nothing(), Q)
assert y.is_Nothing()
# \Cut{Q \Universal} = \Nothing
y = operation(Q, DFA.Universal())
assert y.is_Nothing()
# NOT: \Cut{\Universal Q} = \Universal
if not Q_is_Q_star and not Q_is_Q_plus:
y = operation(Q, DFA.Universal())
assert y.is_Nothing()
return Q_star, Q_plus
def snap_nothing(stream, PatternDict):
return DFA.Nothing()
