def test_nothing_monad_law_associativity(self):
# (m >>= f) >>= g is just like doing m >>= (\x -> f x >>= g)
m = Nothing()
f = lambda x: unit(x + 1000)
g = lambda y: unit(y * 42)
self.assertEqual(m.bind(f).bind(g), m.bind(lambda x: f(x).bind(g)))
def test_nothing_monad_law_associativity(self):
# (m >>= f) >>= g is just like doing m >>= (\x -> f x >>= g)
m = Nothing()
f = lambda x: unit(x+1000)
g = lambda y: unit(y*42)
self.assertEqual(
m.bind(f).bind(g),
m.bind(lambda x: f(x).bind(g))
)
def test_nothing_monad_bind(self):
m = Nothing()
f = lambda x: unit(x*10)
self.assertEqual(
m.bind(f),
Nothing()
)
def test_nothing_monad_bind(self):
m = Nothing()
f = lambda x: unit(x*10)
self.assertEqual(
m.bind(f),
Nothing()
)
def test_nothing_monad_law_right_identity(self):
# m >>= return is no different than just m.
m = Nothing()
self.assertEqual(
m.bind(unit),
m
)
def test_nothing_monad_law_right_identity(self):
# m >>= return is no different than just m.
m = Nothing()
self.assertEqual(
m.bind(unit),
m
)
