int LispObject::Equal(LispObject& aOther)
{
// next line handles the fact that either one is a string
if (String() != aOther.String())
return 0; // return false
//So, no strings.
LispPtr *iter1 = SubList();
LispPtr *iter2 = aOther.SubList();
assert(!!iter1 && !!iter2);
// check all elements in sublist
while (!!(*iter1) && !!(*iter2))
{
if (! (*iter1)->Equal(*(*iter2) ))
return 0;
iter1 = &(*iter1)->Nixed();
iter2 = &(*iter2)->Nixed();
}
//One list longer than the other?
if (!(*iter1) && !(*iter2))
return 1;
return 0;
}
const YacasParamMatcherBase* YacasPatternPredicateBase::MakeParamMatcher(LispEnvironment& aEnvironment, LispObject* aPattern)
{
if (!aPattern)
return nullptr;
if (aPattern->Number(aEnvironment.Precision()))
return new MatchNumber(aPattern->Number(aEnvironment.Precision()));
// Deal with atoms
if (aPattern->String())
return new MatchAtom(aPattern->String());
// Else it must be a sublist
if (aPattern->SubList())
{
// See if it is a variable template:
LispPtr* sublist = aPattern->SubList();
assert(sublist);
LispInt num = InternalListLength(*sublist);
// variable matcher here...
if (num>1)
{
LispObject* head = (*sublist);
if (head->String() == aEnvironment.HashTable().LookUp("_"))
{
LispObject* second = head->Nixed();
if (second->String())
{
LispInt index = LookUp(second->String());
// Make a predicate for the type, if needed
if (num>2)
{
LispPtr third;
LispObject* predicate = second->Nixed();
if (predicate->SubList())
{
InternalFlatCopy(third, *predicate->SubList());
}
else
{
third = (second->Nixed()->Copy());
}
LispObject* last = third;
while (!!last->Nixed())
last = last->Nixed();
last->Nixed() = LispAtom::New(aEnvironment, *second->String());
iPredicates.push_back(LispPtr(LispSubList::New(third)));
}
return new MatchVariable(index);
}
}
}
std::vector<const YacasParamMatcherBase*> matchers;
matchers.reserve(num);
LispIterator iter(*sublist);
for (LispInt i = 0; i < num; ++i, ++iter) {
matchers.push_back(MakeParamMatcher(aEnvironment,iter.getObj()));
assert(matchers[i]);
}
return new MatchSubList(std::move(matchers));
}
return nullptr;
}