def impl_between(engine, lower, upper, varorint, continuation):
if isinstance(varorint, term.Var):
for i in range(lower, upper):
oldstate = engine.heap.branch()
try:
varorint.unify(term.Number(i), engine.heap)
return continuation.call(engine, choice_point=True)
except error.UnificationFailed:
engine.heap.revert(oldstate)
varorint.unify(term.Number(upper), engine.heap)
return continuation.call(engine, choice_point=False)
else:
integer = helper.unwrap_int(varorint)
if not (lower <= integer <= upper):
raise error.UnificationFailed
return continuation.call(engine, choice_point=False)
def impl_between(engine, lower, upper, varorint, continuation):
if isinstance(varorint, term.Var):
for i in range(lower, upper):
oldstate = engine.heap.branch()
try:
varorint.unify(term.Number(i), engine.heap)
return continuation.call(engine, choice_point=True)
except error.UnificationFailed:
engine.heap.revert(oldstate)
varorint.unify(term.Number(upper), engine.heap)
return continuation.call(engine, choice_point=False)
else:
integer = helper.unwrap_int(varorint)
if not (lower <= integer <= upper):
raise error.UnificationFailed
return continuation.call(engine, choice_point=False)
def impl_functor(engine, t, functor, arity):
if helper.is_atomic(t):
functor.unify(t, engine.heap)
arity.unify(term.Number(0), engine.heap)
elif isinstance(t, term.Term):
functor.unify(term.Atom(t.name), engine.heap)
arity.unify(term.Number(len(t.args)), engine.heap)
elif isinstance(t, term.Var):
if isinstance(functor, term.Var):
error.throw_instantiation_error()
a = helper.unwrap_int(arity)
if a < 0:
error.throw_domain_error("not_less_than_zero", arity)
else:
functor = helper.ensure_atomic(functor)
if a == 0:
t.unify(helper.ensure_atomic(functor), engine.heap)
else:
name = helper.unwrap_atom(functor)
t.unify(term.Term(name, [term.Var() for i in range(a)]),
engine.heap)
def impl_functor(engine, t, functor, arity):
if helper.is_atomic(t):
functor.unify(t, engine.heap)
arity.unify(term.Number(0), engine.heap)
elif isinstance(t, term.Term):
functor.unify(term.Atom(t.name), engine.heap)
arity.unify(term.Number(len(t.args)), engine.heap)
elif isinstance(t, term.Var):
if isinstance(functor, term.Var):
error.throw_instantiation_error()
a = helper.unwrap_int(arity)
if a < 0:
error.throw_domain_error("not_less_than_zero", arity)
else:
functor = helper.ensure_atomic(functor)
if a == 0:
t.unify(helper.ensure_atomic(functor), engine.heap)
else:
name = helper.unwrap_atom(functor)
t.unify(
term.Term(name, [term.Var() for i in range(a)]),
engine.heap)
def from_option_list(engine, options):
# XXX add numbervars support
quoted = False
max_depth = 0
ignore_ops = False
number_vars = False
for option in options:
if (not isinstance(option, Term) or len(option.args) != 1):
error.throw_domain_error('write_option', option)
arg = option.args[0]
if option.name == "max_depth":
try:
max_depth = helper.unwrap_int(arg)
except error.CatchableError:
error.throw_domain_error('write_option', option)
elif (not isinstance(arg, Atom) or
(arg.name != "true" and arg.name != "false")):
error.throw_domain_error('write_option', option)
assert 0, "unreachable"
elif option.name == "quoted":
quoted = arg.name == "true"
elif option.name == "ignore_ops":
ignore_ops = arg.name == "true"
return TermFormatter(engine, quoted, max_depth, ignore_ops)
def from_option_list(engine, options):
# XXX add numbervars support
quoted = False
max_depth = 0
ignore_ops = False
number_vars = False
for option in options:
if (not isinstance(option, Term) or len(option.args) != 1):
error.throw_domain_error('write_option', option)
arg = option.args[0]
if option.name == "max_depth":
try:
max_depth = helper.unwrap_int(arg)
except error.CatchableError:
error.throw_domain_error('write_option', option)
elif (not isinstance(arg, Atom)
or (arg.name != "true" and arg.name != "false")):
error.throw_domain_error('write_option', option)
assert 0, "unreachable"
elif option.name == "quoted":
quoted = arg.name == "true"
elif option.name == "ignore_ops":
ignore_ops = arg.name == "true"
return TermFormatter(engine, quoted, max_depth, ignore_ops)
def impl_sub_atom(engine, s, before, length, after, sub, continuation):
# XXX can possibly be optimized
if isinstance(length, term.Var):
startlength = 0
stoplength = len(s) + 1
else:
startlength = helper.unwrap_int(length)
stoplength = startlength + 1
if startlength < 0:
startlength = 0
stoplength = len(s) + 1
if isinstance(before, term.Var):
startbefore = 0
stopbefore = len(s) + 1
else:
startbefore = helper.unwrap_int(before)
stopbefore = startbefore + 1
if startbefore < 0:
startbefore = 0
stopbefore = len(s) + 1
oldstate = engine.heap.branch()
if not isinstance(sub, term.Var):
s1 = helper.unwrap_atom(sub)
if len(s1) >= stoplength or len(s1) < startlength:
raise error.UnificationFailed()
start = startbefore
while True:
try:
try:
b = s.find(s1, start, stopbefore + len(s1)) # XXX -1?
if b < 0:
break
start = b + 1
before.unify(term.Number(b), engine.heap)
after.unify(term.Number(len(s) - len(s1) - b), engine.heap)
length.unify(term.Number(len(s1)), engine.heap)
return continuation.call(engine, choice_point=True)
except:
engine.heap.revert(oldstate)
raise
except error.UnificationFailed:
pass
raise error.UnificationFailed()
if isinstance(after, term.Var):
for b in range(startbefore, stopbefore):
for l in range(startlength, stoplength):
if l + b > len(s):
continue
try:
try:
before.unify(term.Number(b), engine.heap)
after.unify(term.Number(len(s) - l - b), engine.heap)
length.unify(term.Number(l), engine.heap)
sub.unify(term.Atom(s[b:b + l]), engine.heap)
return continuation.call(engine, choice_point=True)
except:
engine.heap.revert(oldstate)
raise
except error.UnificationFailed:
pass
else:
a = helper.unwrap_int(after)
for l in range(startlength, stoplength):
b = len(s) - l - a
assert b >= 0
if l + b > len(s):
continue
try:
try:
before.unify(term.Number(b), engine.heap)
after.unify(term.Number(a), engine.heap)
length.unify(term.Number(l), engine.heap)
sub.unify(term.Atom(s[b:b + l]), engine.heap)
return continuation.call(engine, choice_point=True)
return None
except:
engine.heap.revert(oldstate)
raise
except error.UnificationFailed:
pass
raise error.UnificationFailed()
