def test_unwrap_base_functions():
ontology = _make_mock_ontology()
eq_(str(ontology.unwrap_base_functions(Expression.fromstring(r"unique(sphere)"))),
r"unique(\z1.sphere(z1))")
eq_(str(ontology.unwrap_base_functions(Expression.fromstring(r"cmp_pos(ax_x,unique(sphere),unique(cube))"))),
r"cmp_pos(ax_x,unique(\z1.sphere(z1)),unique(\z1.cube(z1)))")
def test_valid_lambda_expr():
"""
Regression test: valid_lambda_expr was rejecting this good sub-expression at c720b4
"""
ontology = _make_mock_ontology()
eq_(ontology._valid_lambda_expr(Expression.fromstring(r"\b.ltzero(cmp_pos(ax_x,a,b))"), ctx_bound_vars=()), False)
eq_(ontology._valid_lambda_expr(Expression.fromstring(r"\b.ltzero(cmp_pos(ax_x,a,b))"), ctx_bound_vars=(Variable('a'),)), True)
def tableau_test(c, ps=None, verbose=False):
pc = Expression.fromstring(c)
pps = [Expression.fromstring(p) for p in ps] if ps else []
if not ps:
ps = []
print("%s |- %s: %s" %
(", ".join(ps), pc, TableauProver().prove(pc, pps, verbose=verbose)))
def tableau_test(c, ps=None, verbose=False):
pc = Expression.fromstring(c)
pps = [Expression.fromstring(p) for p in ps] if ps else []
if not ps:
ps = []
print(
'%s |- %s: %s'
% (', '.join(ps), pc, TableauProver().prove(pc, pps, verbose=verbose))
)
def folmodel(quiet=False, trace=None):
"""Example of a first-order model."""
global val2, v2, dom2, m2, g2
v2 = [
("adam", "b1"),
("betty", "g1"),
("fido", "d1"),
("girl", set(["g1", "g2"])),
("boy", set(["b1", "b2"])),
("dog", set(["d1"])),
("love", set([("b1", "g1"), ("b2", "g2"), ("g1", "b1"),
("g2", "b1")])),
]
val2 = Valuation(v2)
dom2 = val2.domain
m2 = Model(dom2, val2)
g2 = Assignment(dom2, [("x", "b1"), ("y", "g2")])
if not quiet:
print()
print("*" * mult)
print("Models Demo")
print("*" * mult)
print("Model m2:\n", "-" * 14, "\n", m2)
print("Variable assignment = ", g2)
exprs = ["adam", "boy", "love", "walks", "x", "y", "z"]
parsed_exprs = [Expression.fromstring(e) for e in exprs]
print()
for parsed in parsed_exprs:
try:
print("The interpretation of '%s' in m2 is %s" %
(parsed, m2.i(parsed, g2)))
except Undefined:
print("The interpretation of '%s' in m2 is Undefined" % parsed)
applications = [
("boy", ("adam")),
("walks", ("adam", )),
("love", ("adam", "y")),
("love", ("y", "adam")),
]
for (fun, args) in applications:
try:
funval = m2.i(Expression.fromstring(fun), g2)
argsval = tuple(
m2.i(Expression.fromstring(arg), g2) for arg in args)
print("%s(%s) evaluates to %s" %
(fun, args, argsval in funval))
except Undefined:
print("%s(%s) evaluates to Undefined" % (fun, args))
def folmodel(quiet=False, trace=None):
"""Example of a first-order model."""
global val2, v2, dom2, m2, g2
v2 = [
('adam', 'b1'),
('betty', 'g1'),
('fido', 'd1'),
('girl', set(['g1', 'g2'])),
('boy', set(['b1', 'b2'])),
('dog', set(['d1'])),
('love', set([('b1', 'g1'), ('b2', 'g2'), ('g1', 'b1'),
('g2', 'b1')])),
]
val2 = Valuation(v2)
dom2 = val2.domain
m2 = Model(dom2, val2)
g2 = Assignment(dom2, [('x', 'b1'), ('y', 'g2')])
if not quiet:
print()
print('*' * mult)
print("Models Demo")
print("*" * mult)
print("Model m2:\n", "-" * 14, "\n", m2)
print("Variable assignment = ", g2)
exprs = ['adam', 'boy', 'love', 'walks', 'x', 'y', 'z']
parsed_exprs = [Expression.fromstring(e) for e in exprs]
print()
for parsed in parsed_exprs:
try:
print("The interpretation of '%s' in m2 is %s" %
(parsed, m2.i(parsed, g2)))
except Undefined:
print("The interpretation of '%s' in m2 is Undefined" % parsed)
applications = [
('boy', ('adam')),
('walks', ('adam', )),
('love', ('adam', 'y')),
('love', ('y', 'adam')),
]
for (fun, args) in applications:
try:
funval = m2.i(Expression.fromstring(fun), g2)
argsval = tuple(
m2.i(Expression.fromstring(arg), g2) for arg in args)
print("%s(%s) evaluates to %s" %
(fun, args, argsval in funval))
except Undefined:
print("%s(%s) evaluates to Undefined" % (fun, args))
def example1():
background_theory = [
Expression.fromstring(u"UnitedStates(Henry)"),
Expression.fromstring(u"Young(Henry)")
]
default_rules = [
Expression.fromstring(u"all x.(Young(x) -> -Read(x))"),
Expression.fromstring(u"all x.(UnitedStates(x) -> Read(x))")
]
goal = Expression.fromstring(u"-Read(Henry)")
example_template(1, background_theory, default_rules, goal)
def do_case(index, left, semantics, right, expected_synt, expected_sem):
pfr = PositionalForwardRaiseCombinator(index)
left = lex.parse_category(left)
right = lex.parse_category(right)
ok_(pfr.can_combine(left, right))
eq_(str(next(iter(pfr.combine(left, right)))), expected_synt)
semantics = Expression.fromstring(semantics)
expected_sem = str(Expression.fromstring(expected_sem).simplify())
eq_(str(pfr.update_semantics(semantics)), expected_sem)
def test_config():
a = Expression.fromstring("(walk(j) & sing(j))")
g = Expression.fromstring("walk(j)")
p = Prover9Command(g, assumptions=[a])
p._executable_path = None
p.prover9_search = []
p.prove()
# config_prover9('/usr/local/bin')
print(p.prove())
print(p.proof())
def test_prove(arguments):
"""
Try some proofs and exhibit the results.
"""
for (goal, assumptions) in arguments:
g = Expression.fromstring(goal)
alist = [Expression.fromstring(a) for a in assumptions]
p = Prover9Command(g, assumptions=alist).prove()
for a in alist:
print(" %s" % a)
print("|- %s: %s\n" % (g, p))
def test_config():
a = Expression.fromstring('(walk(j) & sing(j))')
g = Expression.fromstring('walk(j)')
p = Prover9Command(g, assumptions=[a])
p._executable_path = None
p.prover9_search=[]
p.prove()
#config_prover9('/usr/local/bin')
print(p.prove())
print(p.proof())
def test_prove(arguments):
"""
Try some proofs and exhibit the results.
"""
for (goal, assumptions) in arguments:
g = Expression.fromstring(goal)
alist = [Expression.fromstring(a) for a in assumptions]
p = Prover9Command(g, assumptions=alist).prove()
for a in alist:
print(' %s' % a)
print('|- %s: %s\n' % (g, p))
def testResolutionProver():
resolution_test(r'man(x)')
resolution_test(r'(man(x) -> man(x))')
resolution_test(r'(man(x) -> --man(x))')
resolution_test(r'-(man(x) and -man(x))')
resolution_test(r'(man(x) or -man(x))')
resolution_test(r'(man(x) -> man(x))')
resolution_test(r'-(man(x) and -man(x))')
resolution_test(r'(man(x) or -man(x))')
resolution_test(r'(man(x) -> man(x))')
resolution_test(r'(man(x) iff man(x))')
resolution_test(r'-(man(x) iff -man(x))')
resolution_test('all x.man(x)')
resolution_test('-all x.some y.F(x,y) & some x.all y.(-F(x,y))')
resolution_test('some x.all y.sees(x,y)')
p1 = Expression.fromstring(r'all x.(man(x) -> mortal(x))')
p2 = Expression.fromstring(r'man(Socrates)')
c = Expression.fromstring(r'mortal(Socrates)')
print('%s, %s |- %s: %s' % (p1, p2, c, ResolutionProver().prove(c, [p1,p2])))
p1 = Expression.fromstring(r'all x.(man(x) -> walks(x))')
p2 = Expression.fromstring(r'man(John)')
c = Expression.fromstring(r'some y.walks(y)')
print('%s, %s |- %s: %s' % (p1, p2, c, ResolutionProver().prove(c, [p1,p2])))
p = Expression.fromstring(r'some e1.some e2.(believe(e1,john,e2) & walk(e2,mary))')
c = Expression.fromstring(r'some e0.walk(e0,mary)')
print('%s |- %s: %s' % (p, c, ResolutionProver().prove(c, [p])))
def testResolutionProver():
resolution_test(r'man(x)')
resolution_test(r'(man(x) -> man(x))')
resolution_test(r'(man(x) -> --man(x))')
resolution_test(r'-(man(x) and -man(x))')
resolution_test(r'(man(x) or -man(x))')
resolution_test(r'(man(x) -> man(x))')
resolution_test(r'-(man(x) and -man(x))')
resolution_test(r'(man(x) or -man(x))')
resolution_test(r'(man(x) -> man(x))')
resolution_test(r'(man(x) iff man(x))')
resolution_test(r'-(man(x) iff -man(x))')
resolution_test('all x.man(x)')
resolution_test('-all x.some y.F(x,y) & some x.all y.(-F(x,y))')
resolution_test('some x.all y.sees(x,y)')
p1 = Expression.fromstring(r'all x.(man(x) -> mortal(x))')
p2 = Expression.fromstring(r'man(Socrates)')
c = Expression.fromstring(r'mortal(Socrates)')
print('%s, %s |- %s: %s' %
(p1, p2, c, ResolutionProver().prove(c, [p1, p2])))
p1 = Expression.fromstring(r'all x.(man(x) -> walks(x))')
p2 = Expression.fromstring(r'man(John)')
c = Expression.fromstring(r'some y.walks(y)')
print('%s, %s |- %s: %s' %
(p1, p2, c, ResolutionProver().prove(c, [p1, p2])))
p = Expression.fromstring(
r'some e1.some e2.(believe(e1,john,e2) & walk(e2,mary))')
c = Expression.fromstring(r'some e0.walk(e0,mary)')
print('%s |- %s: %s' % (p, c, ResolutionProver().prove(c, [p])))
def testResolutionProver():
resolution_test(r"man(x)")
resolution_test(r"(man(x) -> man(x))")
resolution_test(r"(man(x) -> --man(x))")
resolution_test(r"-(man(x) and -man(x))")
resolution_test(r"(man(x) or -man(x))")
resolution_test(r"(man(x) -> man(x))")
resolution_test(r"-(man(x) and -man(x))")
resolution_test(r"(man(x) or -man(x))")
resolution_test(r"(man(x) -> man(x))")
resolution_test(r"(man(x) iff man(x))")
resolution_test(r"-(man(x) iff -man(x))")
resolution_test("all x.man(x)")
resolution_test("-all x.some y.F(x,y) & some x.all y.(-F(x,y))")
resolution_test("some x.all y.sees(x,y)")
p1 = Expression.fromstring(r"all x.(man(x) -> mortal(x))")
p2 = Expression.fromstring(r"man(Socrates)")
c = Expression.fromstring(r"mortal(Socrates)")
print(f"{p1}, {p2} |- {c}: {ResolutionProver().prove(c, [p1, p2])}")
p1 = Expression.fromstring(r"all x.(man(x) -> walks(x))")
p2 = Expression.fromstring(r"man(John)")
c = Expression.fromstring(r"some y.walks(y)")
print(f"{p1}, {p2} |- {c}: {ResolutionProver().prove(c, [p1, p2])}")
p = Expression.fromstring(r"some e1.some e2.(believe(e1,john,e2) & walk(e2,mary))")
c = Expression.fromstring(r"some e0.walk(e0,mary)")
print(f"{p} |- {c}: {ResolutionProver().prove(c, [p])}")
def do_test(expression, expected_members, expected_non_members):
expr = Expression.fromstring(expression)
split_tuples = []
# iterating with for-loop so that we can catch incremental yields -- easier
# to debug
for part1, part2, dir in ontology.iter_application_splits(expr):
# print("\t\t",part1, "\t", part2, "\t", dir)
split_tuples.append((str(part1), str(part2), dir))
# from pprint import pprint
# pprint(split_tuples)
all_parts = set(part1 for part1, _, _ in split_tuples) | set(
part2 for _, part2, _ in split_tuples)
for el in expected_members:
if el[1] is None:
# just want to assert that a logical expr appears *somewhere*
ok_(el[0] in all_parts, el[0])
else:
# full split specified
ok_(el in split_tuples, el)
for el in expected_non_members:
if el[1] is None:
# just want to assert that a logical expr appears *nowhere*
ok_(el[0] not in all_parts, el[0])
else:
# full split specified
ok_(el not in split_tuples, el)
def test_convert_to_prover9(expr):
"""
Test that parsing works OK.
"""
for t in expr:
e = Expression.fromstring(t)
print(convert_to_prover9(e))
def __init__(self, meaning, glue, indices=None):
if not indices:
indices = set()
if isinstance(meaning, string_types):
self.meaning = Expression.fromstring(meaning)
elif isinstance(meaning, Expression):
self.meaning = meaning
else:
raise RuntimeError(
'Meaning term neither string or expression: %s, %s'
% (meaning, meaning.__class__)
)
if isinstance(glue, string_types):
self.glue = linearlogic.LinearLogicParser().parse(glue)
elif isinstance(glue, linearlogic.Expression):
self.glue = glue
else:
raise RuntimeError(
'Glue term neither string or expression: %s, %s'
% (glue, glue.__class__)
)
self.indices = indices
def test_convert_to_prover9(expr):
"""
Test that parsing works OK.
"""
for t in expr:
e = Expression.fromstring(t)
print(convert_to_prover9(e))
def __init__(self, meaning, glue, indices=None):
if not indices:
indices = set()
if isinstance(meaning, str):
self.meaning = Expression.fromstring(meaning)
elif isinstance(meaning, Expression):
self.meaning = meaning
else:
raise RuntimeError(
"Meaning term neither string or expression: %s, %s"
% (meaning, meaning.__class__)
)
if isinstance(glue, str):
self.glue = linearlogic.LinearLogicParser().parse(glue)
elif isinstance(glue, linearlogic.Expression):
self.glue = glue
else:
raise RuntimeError(
"Glue term neither string or expression: %s, %s"
% (glue, glue.__class__)
)
self.indices = indices
def test_model_induced_functions():
"""
Test evaluating a model with an ontology which has induced functions.
"""
fake_scene = {
"objects": ["foo", "bar"],
}
types = TypeSystem(["a"])
functions = [
types.new_function("test", ("a", "a"), lambda x: True),
types.new_function("test2", ("a", "a"),
Expression.fromstring(r"\x.test(test(x))")),
]
ontology = Ontology(types, functions, [])
model = Model(scene=fake_scene, ontology=ontology)
cases = [
("Test basic call of an abstract function", r"\a.test2(a)", {
"foo": True,
"bar": True
}),
("Test embedded call of an abstract function", r"\a.test(test2(a))", {
"foo": True,
"bar": True
}),
]
def test(msg, expr, expected):
eq_(model.evaluate(Expression.fromstring(expr)), expected, msg=msg)
for msg, expr, expected in cases:
yield test, msg, expr, expected
def test_read_ec_sexpr_de_bruijn():
"""
properly handle de Bruijn indexing in EC lambda expressions.
"""
expr, bound_vars = read_ec_sexpr(
"(lambda ((lambda ($0 (lambda $0))) (lambda ($1 $0))))")
print(expr)
eq_(expr, Expression.fromstring(r"\A.((\B.B(\C.C))(\C.A(C)))"))
def do_test(expr, assert_in, assert_not_in):
expr = Expression.fromstring(expr)
subexprs = [str(e) for e, _ in get_subexpressions(expr)]
for e in assert_in:
ok_(e in subexprs, e)
for e in assert_not_in:
ok_(e not in subexprs, e)
def demo():
test_clausify()
print()
testResolutionProver()
print()
p = Expression.fromstring('man(x)')
print(ResolutionProverCommand(p, [p]).prove())
def test_read_ec_sexpr_nested():
"""
read_ec_sexpr should support reading in applications where the function
itself is an expression (i.e. there is some not-yet-reduced beta reduction
candidate).
"""
expr, bound_vars = read_ec_sexpr("(lambda ((lambda (foo $0)) $0))")
eq_(expr, Expression.fromstring(r"\a.((\b.foo(b))(a))"))
def do_test(expr, extra_signature, expected):
expr = Expression.fromstring(expr)
if expected == None:
assert_raises(TypeException, ontology.typecheck, expr, extra_signature)
else:
ontology.typecheck(expr, extra_signature)
eq_(expr.type, expected)
def demo():
test_clausify()
print()
testResolutionProver()
print()
p = Expression.fromstring("man(x)")
print(ResolutionProverCommand(p, [p]).prove())
def test_extract_lambda(): """ `extract_lambda` should support all possible orderings of the variables it encounters. """ expr = Expression.fromstring(r"foo(\a.a,\a.a)") extracted = B.extract_lambda(expr) eq_(len(extracted), 2)
def satdemo(trace=None):
"""Satisfiers of an open formula in a first order model."""
print()
print("*" * mult)
print("Satisfiers Demo")
print("*" * mult)
folmodel(quiet=True)
formulas = [
"boy(x)",
"(x = x)",
"(boy(x) | girl(x))",
"(boy(x) & girl(x))",
"love(adam, x)",
"love(x, adam)",
"-(x = adam)",
"exists z22. love(x, z22)",
"exists y. love(y, x)",
"all y. (girl(y) -> love(x, y))",
"all y. (girl(y) -> love(y, x))",
"all y. (girl(y) -> (boy(x) & love(y, x)))",
"(boy(x) & all y. (girl(y) -> love(x, y)))",
"(boy(x) & all y. (girl(y) -> love(y, x)))",
"(boy(x) & exists y. (girl(y) & love(y, x)))",
"(girl(x) -> dog(x))",
"all y. (dog(y) -> (x = y))",
"exists y. love(y, x)",
"exists y. (love(adam, y) & love(y, x))",
]
if trace:
print(m2)
for fmla in formulas:
print(fmla)
Expression.fromstring(fmla)
parsed = [Expression.fromstring(fmla) for fmla in formulas]
for p in parsed:
g2.purge()
print("The satisfiers of '%s' are: %s" %
(p, m2.satisfiers(p, "x", g2, trace)))
def test_iter_expressions_with_used_constants(): ontology = _make_simple_mock_ontology() ontology.register_expressions([Expression.fromstring(r"\z1.and_(foo(z1),baz)")]) expressions = set(ontology.iter_expressions(max_depth=3, use_unused_constants=True)) expression_strs = list(map(str, expressions)) ok_(r"foo(qux)" in expression_strs, "Use of new constant variable") ok_(r"baz" not in expression_strs, "Cannot use used constant variable")
def satdemo(trace=None):
"""Satisfiers of an open formula in a first order model."""
print()
print('*' * mult)
print("Satisfiers Demo")
print('*' * mult)
folmodel(quiet=True)
formulas = [
'boy(x)',
'(x = x)',
'(boy(x) | girl(x))',
'(boy(x) & girl(x))',
'love(adam, x)',
'love(x, adam)',
'-(x = adam)',
'exists z22. love(x, z22)',
'exists y. love(y, x)',
'all y. (girl(y) -> love(x, y))',
'all y. (girl(y) -> love(y, x))',
'all y. (girl(y) -> (boy(x) & love(y, x)))',
'(boy(x) & all y. (girl(y) -> love(x, y)))',
'(boy(x) & all y. (girl(y) -> love(y, x)))',
'(boy(x) & exists y. (girl(y) & love(y, x)))',
'(girl(x) -> dog(x))',
'all y. (dog(y) -> (x = y))',
'exists y. love(y, x)',
'exists y. (love(adam, y) & love(y, x))'
]
if trace:
print(m2)
for fmla in formulas:
print(fmla)
Expression.fromstring(fmla)
parsed = [Expression.fromstring(fmla) for fmla in formulas]
for p in parsed:
g2.purge()
print("The satisfiers of '%s' are: %s" % (p, m2.satisfiers(p, 'x', g2, trace)))
def test_read_ec_sexpr():
ontology = _make_simple_mock_ontology()
expr, bound_vars = ontology.read_ec_sexpr(
"(lambda (lambda (lambda (and_ (threeplace $0 qux $1) (and_ (foo $2) baz)))))"
)
eq_(
expr,
Expression.fromstring(
r"\a b c.and_(threeplace(c,qux,b),and_(foo(a),baz))"))
eq_(len(bound_vars), 3)
def test_read_ec_sexpr_de_bruijn():
"""
properly handle de Bruijn indexing in EC lambda expressions.
"""
ontology = _make_simple_mock_ontology()
expr, bound_vars = ontology.read_ec_sexpr(
"(lambda ((lambda ($0 (lambda $0))) (lambda ($1 $0))))")
print(expr)
eq_(expr, Expression.fromstring(r"\A.((\B.B(\C.C))(\C.A(C)))"))
eq_(len(bound_vars), 4)
def test_read_ec_sexpr_nested():
"""
read_ec_sexpr should support reading in applications where the function
itself is an expression (i.e. there is some not-yet-reduced beta reduction
candidate).
"""
ontology = _make_simple_mock_ontology()
expr, bound_vars = ontology.read_ec_sexpr(
"(lambda ((lambda (abc $0)) $0))")
eq_(expr, Expression.fromstring(r"\a.((\b.abc(b))(a))"))
eq_(len(bound_vars), 2)
def test_model_stored_partial_application():
types = TypeSystem(["obj"])
functions = [
types.new_function("lotsofargs", ("obj", "obj", "obj"),
lambda a, b: b),
]
constants = [
types.new_constant("obj1", "obj"),
types.new_constant("obj2", "obj"),
]
ontology = Ontology(types, functions, constants)
ontology.add_functions([
types.new_function("partial", ("obj", "obj"),
Expression.fromstring(r"lotsofargs(obj2)"))
])
scene = {"objects": []}
model = Model(scene, ontology)
eq_(model.evaluate(Expression.fromstring(r"partial(obj1)")), "obj1")
def folmodel(quiet=False, trace=None):
"""Example of a first-order model."""
global val2, v2, dom2, m2, g2
v2 = [('adam', 'b1'), ('betty', 'g1'), ('fido', 'd1'),\
('girl', set(['g1', 'g2'])), ('boy', set(['b1', 'b2'])), ('dog', set(['d1'])),
('love', set([('b1', 'g1'), ('b2', 'g2'), ('g1', 'b1'), ('g2', 'b1')]))]
val2 = Valuation(v2)
dom2 = val2.domain
m2 = Model(dom2, val2)
g2 = Assignment(dom2, [('x', 'b1'), ('y', 'g2')])
if not quiet:
print()
print('*' * mult)
print("Models Demo")
print("*" * mult)
print("Model m2:\n", "-" * 14,"\n", m2)
print("Variable assignment = ", g2)
exprs = ['adam', 'boy', 'love', 'walks', 'x', 'y', 'z']
parsed_exprs = [Expression.fromstring(e) for e in exprs]
print()
for parsed in parsed_exprs:
try:
print("The interpretation of '%s' in m2 is %s" % (parsed, m2.i(parsed, g2)))
except Undefined:
print("The interpretation of '%s' in m2 is Undefined" % parsed)
applications = [('boy', ('adam')), ('walks', ('adam',)), ('love', ('adam', 'y')), ('love', ('y', 'adam'))]
for (fun, args) in applications:
try:
funval = m2.i(Expression.fromstring(fun), g2)
argsval = tuple(m2.i(Expression.fromstring(arg), g2) for arg in args)
print("%s(%s) evaluates to %s" % (fun, args, argsval in funval))
except Undefined:
print("%s(%s) evaluates to Undefined" % (fun, args))
def do_test(expr, assert_in):
expr = Expression.fromstring(expr)
splits = []
for left, right, dir in ontology.iter_application_splits(expr):
splits.append((str(left), str(right), dir))
print("\t", left, right, dir)
# splits = list(ontology.iter_application_splits(expr))
# splits = [(str(left), str(right), dir) for left, right, dir in splits]
# from pprint import pprint
# pprint(splits)
for el in assert_in:
ok_(el in splits, "%s not in splits" % (el, ))
def _test_application_split_sound(expr, ontology):
"""
Evaluate soundness of `iter_application_splits` for a particular expression.
"""
if isinstance(expr, str):
expr = Expression.fromstring(expr)
subexprs = [str(x) for x, _ in get_subexpressions(expr)]
for part1, part2, dir in ontology.iter_application_splits(expr):
arg1, arg2 = (part1, part2) if dir == "/" else (part2, part1)
reapplied = str(ApplicationExpression(arg1, arg2).simplify())
ok_(reapplied in subexprs,
"%s %s %s --> %s" % (part1, dir, part2, reapplied))
def example2():
background_theory = [
Expression.fromstring(u"Personal(y)"),
Expression.fromstring(u"all x.(Personal(x) -> Interest(x))"),
Expression.fromstring(u"all x.(QRI(x) -> Personal(x))")
]
default_rules = [
Expression.fromstring(u"all x.(QRI(x) -> Deductible(x))"),
Expression.fromstring(u"all x.(Personal(x) -> -Deductible(x))"),
Expression.fromstring(u"all x.(Interest(x) -> Deductible(x))")
]
goal = Expression.fromstring(u"-Deductible(y)")
example_template(2, background_theory, default_rules, goal)
def fromstring(lex_str, include_semantics=False):
"""
Convert string representation into a lexicon for CCGs.
"""
CCGVar.reset_id()
primitives = []
families = {}
entries = defaultdict(list)
for line in lex_str.splitlines():
# Strip comments and leading/trailing whitespace.
line = COMMENTS_RE.match(line).groups()[0].strip()
if line == "":
continue
if line.startswith(':-'):
# A line of primitive categories.
# The first one is the target category
# ie, :- S, N, NP, VP
primitives = primitives + [
prim.strip() for prim in line[2:].strip().split(',')
]
else:
# Either a family definition, or a word definition
(ident, sep, rhs) = LEX_RE.match(line).groups()
(catstr, semantics_str) = RHS_RE.match(rhs).groups()
(cat, var) = augParseCategory(catstr, primitives, families)
if sep == '::':
# Family definition
# ie, Det :: NP/N
families[ident] = (cat, var)
else:
semantics = None
if include_semantics is True:
if semantics_str is None:
raise AssertionError(
line
+ " must contain semantics because include_semantics is set to True"
)
else:
semantics = Expression.fromstring(
SEMANTICS_RE.match(semantics_str).groups()[0]
)
# Word definition
# ie, which => (N\N)/(S/NP)
entries[ident].append(Token(ident, cat, semantics))
return CCGLexicon(primitives[0], primitives, families, entries)
def load_fol(s):
"""
Temporarily duplicated from ``nltk.sem.util``.
Convert a file of first order formulas into a list of ``Expression`` objects.
:param s: the contents of the file
:type s: str
:return: a list of parsed formulas.
:rtype: list(Expression)
"""
statements = []
for linenum, line in enumerate(s.splitlines()):
line = line.strip()
if line.startswith('#') or line=='': continue
try:
statements.append(Expression.fromstring(line))
except Exception:
raise ValueError('Unable to parse line %s: %s' % (linenum, line))
return statements
def evaluate(self, expr, g, trace=None):
"""
Read input expressions, and provide a handler for ``satisfy``
that blocks further propagation of the ``Undefined`` error.
:param expr: An ``Expression`` of ``logic``.
:type g: Assignment
:param g: an assignment to individual variables.
:rtype: bool or 'Undefined'
"""
try:
parsed = Expression.fromstring(expr)
value = self.satisfy(parsed, g, trace=trace)
if trace:
print()
print("'%s' evaluates to %s under M, %s" % (expr, value, g))
return value
except Undefined:
if trace:
print()
print("'%s' is undefined under M, %s" % (expr, g))
return 'Undefined'
def resolution_test(e):
f = Expression.fromstring(e)
t = ResolutionProver().prove(f)
print('|- %s: %s' % (f, t))