def test_enumerate_vars_of_bound_var():
from prolog.interpreter.memo import EnumerationMemo
h = Heap()
X = h.newvar()
X.setvalue(Callable.build("a"), h)
t1 = Callable.build("f", [X])
memo = EnumerationMemo()
t2 = t1.enumerate_vars(memo)
assert is_term(t2)
assert t2.signature().eq(t1.signature())
assert t1.argument_at(0).dereference(None) is t2.argument_at(0)
def test_enumerate_vars_of_bound_var():
from prolog.interpreter.memo import EnumerationMemo
h = Heap()
X = h.newvar()
X.setvalue(Callable.build("a"), h)
t1 = Callable.build("f", [X])
memo = EnumerationMemo()
t2 = t1.enumerate_vars(memo)
assert is_term(t2)
assert t2.signature().eq(t1.signature())
assert t1.argument_at(0).dereference(None) is t2.argument_at(0)
def test_cyclic_term():
h = Heap()
X = h.newvar()
t = Callable.build("f", [X], heap=h)
t.unify(X, h)
Y = h.newvar()
t2 = Callable.build("f", [Y], heap=h)
t2.unify(Y, h)
t.unify(t2, h) # does not crash
X.unify(Y, h) # does not crash
def test_callable_build_removes_unneeded_vars():
h1 = Heap()
v1 = h1.newvar()
v1.binding = 1
h2 = h1.branch()
v2 = h2.newvar()
v2.binding = 2
t = Callable.build("hello", [v1, v2], heap=h2)
assert t.argument_at(0) is v1
assert t.argument_at(1) == 2
def test_cyclic_term():
h = Heap()
X = h.newvar()
t = Callable.build("f", [X], heap=h)
t.unify(X, h)
Y = h.newvar()
t2 = Callable.build("f", [Y], heap=h)
t2.unify(Y, h)
t.unify(t2, h) # does not crash
X.unify(Y, h) # does not crash
def test_callable_build_removes_unneeded_vars():
h1 = Heap()
v1 = h1.newvar()
v1.binding = 1
h2 = h1.branch()
v2 = h2.newvar()
v2.binding = 2
t = Callable.build("hello", [v1, v2], heap=h2)
assert t.argument_at(0) is v1
assert t.argument_at(1) == 2
def test_copy_standardize_apart():
heap = Heap()
Z = NumberedVar(0)
env = [None]
t1, f1 = Z.copy_standardize_apart(heap, env)
t2, f2 = Z.copy_standardize_apart(heap, env)
assert not f1
assert not f2
assert isinstance(t1, Var)
assert t1 is t2
env = [Number(1)]
t1, f1 = Z.copy_standardize_apart(heap, env)
assert isinstance(t1, Number)
t2, f2 = Z.copy_standardize_apart(heap, env)
assert t1 is t2
assert not f1
assert not f2
Z = NumberedVar(-1)
t1, f1 = Z.copy_standardize_apart(heap, [None])
t2, f2 = Z.copy_standardize_apart(heap, [None])
assert isinstance(t1, Var)
assert isinstance(t2, Var)
assert t1 is not t2
assert not f1
assert not f2
def test_run():
e = Engine()
e.add_rule(Callable.build("f", [Callable.build("a"), Callable.build("b")]))
X = BindingVar()
Y = BindingVar()
c = Callable.build("f", [X, X])
e.add_rule(c)
c2 = Callable.build(":-", [Callable.build("f", [X, Y]),
Callable.build("f", [Y, X])])
e.add_rule(c2)
hp = Heap()
X = hp.newvar()
c3 = Callable.build("f", [Callable.build("b"), X])
e.run_query_in_current(c3)
assert X.dereference(hp).name()== "b"
query = Callable.build("f", [Callable.build("b"), Callable.build("a")])
e.run_query_in_current(query)
def test_run():
e = Engine()
e.add_rule(Callable.build("f", [Callable.build("a"), Callable.build("b")]))
X = BindingVar()
Y = BindingVar()
c = Callable.build("f", [X, X])
e.add_rule(c)
c2 = Callable.build(
":-", [Callable.build("f", [X, Y]),
Callable.build("f", [Y, X])])
e.add_rule(c2)
hp = Heap()
X = hp.newvar()
c3 = Callable.build("f", [Callable.build("b"), X])
e.run_query_in_current(c3)
assert X.dereference(hp).name() == "b"
query = Callable.build("f", [Callable.build("b"), Callable.build("a")])
e.run_query_in_current(query)
def test_term():
X = BindingVar()
Y = BindingVar()
t1 = Callable.build("f", [Callable.build("hallo"), X])
t2 = Callable.build("f", [Y, Callable.build("HALLO")])
heap = Heap()
print t1, t2
t1.unify(t2, heap)
assert X.dereference(heap).name() == "HALLO"
assert Y.dereference(heap).name() == "hallo"
def test_var():
b = BindingVar()
heap = Heap()
b.unify(Callable.build("hallo"), heap)
assert b.dereference(heap).name() == "hallo"
a = BindingVar()
b = BindingVar()
a.unify(b, heap)
a.unify(Callable.build("hallo"), heap)
assert a.dereference(heap).name() == "hallo"
assert b.dereference(heap).name() == "hallo"
def test_unify_and_standardize_apart():
heap = Heap()
X = BindingVar()
Y = BindingVar()
Z = NumberedVar(0)
t1 = Callable.build(
"f", [Z, Callable.build("g", [Z, Callable.build("h")]), Z])
t2 = Callable.build("f", [Callable.build("i"), X, Y])
env = [None]
t1.unify_and_standardize_apart(t2, heap, env)
Z = NumberedVar(-1)
Z.unify_and_standardize_apart(t2, heap, [])
def test_copy_standardize_apart_term():
heap = Heap()
Z = NumberedVar(0)
t = Callable.build("f", [Z, Z])
t2 = t.copy_standardize_apart(heap, [None])
assert isinstance(t2.argument_at(0), Var)
assert t2.argument_at(0) is t2.argument_at(1)
t2 = t.copy_standardize_apart(heap, [Number(1)])
assert isinstance(t2.argument_at(0), Number)
assert t2.argument_at(0) is t2.argument_at(1)
Z = NumberedVar(-1)
t = Callable.build("f", [Z, Z])
t2 = t.copy_standardize_apart(heap, [None])
assert isinstance(t2.argument_at(0), Var)
assert isinstance(t2.argument_at(1), Var)
assert t2.argument_at(0) is not t2.argument_at(1)
def test_recursive():
b = BindingVar()
heap = Heap()
b.unify(Callable.build("hallo", [b]), heap)
def test_unify_var():
b = BindingVar()
heap = Heap()
b.unify(b, heap)
b.unify(Callable.build("hallo"), heap)
py.test.raises(UnificationFailed, b.unify, Callable.build("bye"), heap)
def test_copy_standardize_apart_ground_term():
heap = Heap()
t = Callable.build("f", [Number(1), Callable.build("g")])
t2, f2 = t.copy_standardize_apart(heap, [None])
assert f2
assert t2 is t
