def test_addmethod():
D = MultiMethod('add')
D.add((int, int), lambda x, y: x + y)
D.add((float, float), lambda x, y: x + y)
assert D(1, 2) == 3
assert D(1.0, 2.0) == 3.0
def test_arguments():
f = MultiMethod('f')
@f.register(int, int)
@f.register(int)
def foo(a, b=10):
return a - b
assert foo(10, 3) == 7
assert foo(5) == -5
assert foo(b=2, a=1) == -1
assert foo(a=1, b=2) == -1
