def assocunify(u, v, s, eq=core.eq):
""" Associative Unification
See Also:
eq_assoccomm
"""
res = unify(u, v, s)
if res is not False:
return (res,) # TODO: iterate through all possibilities
if isinstance(u, tuple) and isinstance(v, tuple):
uop, u = u[0], u[1:]
vop, v = v[0], v[1:]
s = unify(uop, vop, s)
if s is False:
raise StopIteration()
op = walk(uop, s)
sm, lg = (u, v) if len(u) <= len(v) else (v, u)
parts = (groupsizes_to_partition(*gsizes) for gsizes
in groupsizes(len(lg), len(sm)))
ops = (makeops(op, partition(lg, part)) for part in parts)
goal = condeseq([(eq, a, b) for a, b in zip(sm, lg2)] for lg2 in ops)
return goaleval(goal)(s)
return ()
def test_groupsizes():
assert set(groupsizes(4, 2)) == set(((1, 3), (2, 2), (3, 1)))
assert set(groupsizes(5, 2)) == set(((1, 4), (2, 3), (3, 2), (4, 1)))
assert set(groupsizes(4, 1)) == set([(4,)])
assert set(groupsizes(4, 4)) == set([(1, 1, 1, 1)])
def assocsized(op, tail, n):
""" All associative combinations of x in n groups """
gsizess = groupsizes(len(tail), n)
partitions = (groupsizes_to_partition(*gsizes) for gsizes in gsizess)
return (makeops(op, partition(tail, part)) for part in partitions)
def test_groupsizes():
assert set(groupsizes(4, 2)) == set(((1, 3), (2, 2), (3, 1)))
assert set(groupsizes(5, 2)) == set(((1, 4), (2, 3), (3, 2), (4, 1)))
assert set(groupsizes(4, 1)) == set([(4,)])
assert set(groupsizes(4, 4)) == set([(1, 1, 1, 1)])
