def test_numeral():
from prolog.interpreter.term import Callable, Atom, BindingVar
from prolog.interpreter.continuation import Engine
t = parse_file("""
numeral(null). % end of line comment
numeral(succ(X)) :- numeral(X). % another one
add_numeral(X, null, X).
add_numeral(X, succ(Y), Z) :- add_numeral(succ(X), Y, Z).
greater_than(succ(null), null).
greater_than(succ(X), null) :- greater_than(X, null).
greater_than(succ(X), succ(Y)) :- greater_than(X, Y).
""")
builder = TermBuilder()
facts = builder.build(t)
e = Engine()
m = e.modulewrapper
for fact in facts:
print fact
e.add_rule(fact)
assert m.modules["user"].lookup(Signature.getsignature("add_numeral", 3)).rulechain.head.argument_at(1).name() == "null"
four = Callable.build("succ", [Callable.build("succ", [Callable.build("succ",
[Callable.build("succ", [Callable.build("null")])])])])
e.run_query_in_current(parse_query_term("numeral(succ(succ(null)))."))
term = parse_query_term(
"""add_numeral(succ(succ(null)), succ(succ(null)), X).""")
e.run_query_in_current(term)
hp = Heap()
var = BindingVar().dereference(hp)
# does not raise
var.unify(four, hp)
term = parse_query_term(
"""greater_than(succ(succ(succ(null))), succ(succ(null))).""")
e.run_query_in_current(term)
def test_unwrap_list():
a = Callable.build("a")
l = unwrap_list(Callable.build(".",
[a, Callable.build("[]")]))
assert len(l) == 1
assert l[0] is a
v1 = BindingVar()
a1 = Callable.build("a")
l1 = unwrap_list(Callable.build(".",
[v1, Callable.build(".", [a1, Callable.build("[]")])]))
assert l1 == [v1, a1]
empty = Callable.build("[]")
v2 = BindingVar()
l2 = Callable.build(".", [a, v2])
v2.unify(empty, Heap())
unwrapped = unwrap_list(l2)
assert unwrapped == [a]
v3 = BindingVar()
v4 = BindingVar()
b = Callable.build("b")
h = Heap()
l3 = Callable.build(".", [a, v3])
v3.unify(Callable.build(".", [b, v4]), h)
v4.unify(Callable.build("[]"), h)
unwrapped2 = unwrap_list(l3)
assert unwrapped2 == [a, b]
def test_numeral():
from prolog.interpreter.term import Callable, Atom, BindingVar
from prolog.interpreter.continuation import Engine
t = parse_file("""
numeral(null). % end of line comment
numeral(succ(X)) :- numeral(X). % another one
add_numeral(X, null, X).
add_numeral(X, succ(Y), Z) :- add_numeral(succ(X), Y, Z).
greater_than(succ(null), null).
greater_than(succ(X), null) :- greater_than(X, null).
greater_than(succ(X), succ(Y)) :- greater_than(X, Y).
""")
builder = TermBuilder()
facts = builder.build(t)
e = Engine()
m = e.modulewrapper
for fact in facts:
print fact
e.add_rule(fact)
assert m.modules["user"].lookup(Signature.getsignature(
"add_numeral", 3)).rulechain.head.argument_at(1).name() == "null"
four = Callable.build("succ", [
Callable.build("succ", [
Callable.build("succ",
[Callable.build("succ", [Callable.build("null")])])
])
])
e.run_query_in_current(parse_query_term("numeral(succ(succ(null)))."))
term = parse_query_term(
"""add_numeral(succ(succ(null)), succ(succ(null)), X).""")
e.run_query_in_current(term)
hp = Heap()
var = BindingVar().dereference(hp)
# does not raise
var.unify(four, hp)
term = parse_query_term(
"""greater_than(succ(succ(succ(null))), succ(succ(null))).""")
e.run_query_in_current(term)
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_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_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_simple_hooks():
hp = Heap()
v = BindingVar()
a = AttVar()
v.unify(a, hp)
assert hp.hook is None
v.unify(Number(1), hp)
assert hp.hook.attvar == a
hp = Heap()
v1 = BindingVar()
v2 = BindingVar()
a1 = AttVar()
a2 = AttVar()
v1.unify(a1, hp)
assert hp.hook is None
v2.unify(a2, hp)
assert hp.hook is None
v1.unify(v2, hp)
assert hp.hook.attvar == a1
hp = Heap()
v1 = BindingVar()
v2 = BindingVar()
v3 = BindingVar()
a1 = AttVar()
a2 = AttVar()
a3 = AttVar()
v1.unify(a1, hp)
v2.unify(a2, hp)
v3.unify(a3, hp)
v1.unify(v2, hp)
v2.unify(v3, hp)
assert hp.hook.attvar == a2
assert hp.hook.next.attvar == a1
assert hp.hook.next.next is None
hp = Heap()
v1 = BindingVar()
v2 = BindingVar()
a1 = AttVar()
a2 = AttVar()
v1.unify(a1, hp)
v2.unify(a2, hp)
assert hp.hook is None
v1.unify(v2, hp)
assert hp.hook.attvar == a1
v1.unify(Number(1), hp)
assert hp.hook.attvar == a2
assert hp.hook.next.attvar == a1
assert hp.hook.next.next is None
hp = Heap()
v1 = BindingVar()
v2 = BindingVar()
a1 = AttVar()
a2 = AttVar()
v1.unify(a1, hp)
v2.unify(a2, hp)
t1 = Callable.build("f", [v1, v2])
t2 = Callable.build("f", [Atom("a"), Atom("b")])
t1.unify(t2, hp)
assert hp.hook.attvar == a2
assert hp.hook.next.attvar == a1
assert hp.hook.next.next is None
hp = Heap()
v = BindingVar()
av = AttVar()
v.unify(av, hp)
assert hp.hook is None
a = Callable.build("a")
v.unify(a, hp)
assert hp.hook.attvar == av
v.unify(a, hp)
assert hp.hook.attvar == av
assert hp.hook.next is None
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)
