CharSet* Action::Symbols(Tab *tab) {
CharSet *s;
if (typ == Node::clas)
s = tab->CharClassSet(sym)->Clone();
else {
s = new CharSet(); s->Set(sym);
}
return s;
}
void CharSet::Subtract(CharSet *s) {
CharSet *x = new CharSet();
Range *p = head;
while (p != NULL) {
for (int i = p->from; i <= p->to; i++)
if (!s->Get(i)) x->Set(i);
Range *del = p;
p = p->next;
delete del;
}
head = x->head;
x->head = NULL;
delete x;
}
void CharSet::Subtract(const CharSet& b)
{
CharSet tmp;
Range *p = head;
while (p != NULL)
{
for (int i = p->from; i <= p->to; i++)
{
if (!b.Get(i))
{
tmp.Set(i);
}
}
// cleanup old storage - as per Clear
Range *del = p;
p = p->next;
delete del;
}
head = tmp.head;
tmp.head = NULL; // avoid double deletion
}
