def run(cls, description):
""" generated source for method run """
# This class is not put together in any "optimal" way, so it's left in
# an unpolished state for now. A better version would use estimates of
# the impact of breaking apart rules. (It also needs to stop itself from
# making multiple new relations with the same meaning.)
# This version will be rather advanced.
# In particular, it will try to incorporate
# 1) More thorough scanning for condensations;
# 2) Condensations that are only safe to perform because of mutexes.
# TODO: Don't perform condensations on stuff like (add _ _ _)...
# In general, don't perform condensations where the headroom is huge?
# Better yet... DON'T perform condensations on recursive functions!
# As for headroom... maybe make sure that # of vars eliminated > # "kept"
# Or make sure none are kept? Use directional connected components?
description = GdlCleaner.run(description)
description = DeORer.run(description)
description = VariableConstrainer.replaceFunctionValuedVariables(description)
# How do we define a condensation, and what needs to be true in it?
# Definition: A condensation set is a set of conjuncts of a
# sentence.
# Restrictions:
# 1) There must be some variable not in the head of the sentence that
# appears exclusively in the condensation set. (This means we can
# easily find sets one of which must be a condensation set.)
# 2) For any variable appearing in a distinct or not conjunct in the set,
# there must be a positive conjunct in the set also containing that
# variable. This does apply to variables found in the head.
# 3) There must be at least one non-distinct literal outside the
# condensation set.
# How mutexes work:
# Say we have a rule
# (<= (r1 ?b)
# (r2 ?a ?b ?c)
# (r3 ?b ?c)
# (r4 ?a)
# (r5 ?c))
# If we wanted to factor out ?a, we'd normally have to do
# (<= (r6 ?b ?c)
# * (r2 ?a ?b ?c)
# * (r4 ?a))
# * (<= (r1 ?b)
# * (r6 ?b ?c)
# * (r3 ?b ?c)
# * (r5 ?c))
# * But if we know r2 is a mutex, instead we can do (notice r2 splitting):
# * (<= (r6 ?b)
# * (r2 ?a ?b ?c)
# * (r4 ?a))
# * (<= (r1 ?b)
# * (r2 ?a ?b ?c)
# * (r6 ?b)
# * (r3 ?b ?c)
# * (r5 ?c))
# * Which in turn becomes:
# * (<= (r6 ?b)
# * (r2 ?a ?b ?c)
# * (r4 ?a))
# * (<= (r7 ?b)
# * (r2 ?a ?b ?c)
# * (r3 ?b ?c)
# * (r5 ?c))
# * (<= (r1 ?b)
# * (r6 ?b)
# * (r7 ?b))
# * Both r6 and r7 can be further condensed to ignore ?c and ?a,
# * respectively. What just happened?
# * 1) The condensation set for ?a included the mutex r2.
# * 2) r2 (by itself) would have required ?c to be included as an
# * argument passed back to the original rule, which is undesirable.
# * Instead, as it's a mutex, we leave a copy in the original rule
# * and don't include the ?c.
# *
# * So, what kind of algorithm can we find to solve this task?
#
newDescription = ArrayList()
rulesToAdd = LinkedList()
for gdl in description:
if isinstance(gdl, (GdlRule, )):
rulesToAdd.add(gdl)
else:
newDescription.add(gdl)
# Don't use the model indiscriminately; it reflects the old description,
# not necessarily the new one
model = SentenceDomainModelFactory.createWithCartesianDomains(description)
model = SentenceDomainModelOptimizer.restrictDomainsToUsefulValues(model)
sentenceNameSource = UnusedSentenceNameSource.create(model)
constantChecker = ConstantCheckerFactory.createWithForwardChaining(model)
constantForms = model.getConstantSentenceForms()
ConcurrencyUtils.checkForInterruption()
curDescription = Lists.newArrayList(description)
while not rulesToAdd.isEmpty():
if isRecursive(curRule):
# Don't mess with it!
newDescription.add(curRule)
continue
if SentenceModelUtils.inSentenceFormGroup(curRuleHead, constantForms):
newDescription.add(curRule)
continue
ConcurrencyUtils.checkForInterruption()
if condensationSet != None:
rulesToAdd.addAll(newRules)
# Since we're making only small changes, we can readjust
# the model as we go, instead of recomputing it
replacementDescription.removeAll(oldRules)
replacementDescription.addAll(newRules)
curDescription = replacementDescription
model = augmentModelWithNewForm(model, newRules)
else:
newDescription.add(curRule)
return newDescription
