void REParser::appendQuantifier(const QString & token, TokenList & q) {
const QString s(token.mid(1, token.size()-2));
int i(s.indexOf(QChar(',')));
if(i<0) {
i=s.toInt();
q.appendQUANTIFIER(Quantifier(i, i));
} else {
const QString l(s.left(i));
const QString r(s.mid(i+1));
int min(0);
int max(-1);
if(l.size())min=l.toInt();
if(r.size())max=r.toInt();
q.appendQUANTIFIER(Quantifier(min, max));
}
}
ALWAYS_INLINE Quantifier Parser::consumeGreedyQuantifier()
{
switch (peek()) {
case '?':
consume();
return Quantifier(Quantifier::Greedy, 0, 1);
case '*':
consume();
return Quantifier(Quantifier::Greedy, 0);
case '+':
consume();
return Quantifier(Quantifier::Greedy, 1);
case '{': {
SavedState state(*this);
consume();
// Accept: {n}, {n,}, {n,m}.
// Reject: {n,m} where n > m.
// Ignore: Anything else, such as {n, m}.
if (!peekIsDigit()) {
state.restore();
return Quantifier();
}
unsigned min = consumeNumber();
unsigned max = min;
if (peek() == ',') {
consume();
max = peekIsDigit() ? consumeNumber() : Quantifier::Infinity;
}
if (peek() != '}') {
state.restore();
return Quantifier();
}
consume();
if (min > max) {
setError(QuantifierOutOfOrder);
return Quantifier(Quantifier::Error);
}
return Quantifier(Quantifier::Greedy, min, max);
}
default:
return Quantifier(); // No quantifier.
}
}
ReSyntaxExprNode* ReSyntaxTreeBuilder::Factor()
{
ReSyntaxExprNode* res;
if (tokenizer.Match(__R('(')))
{
if ((tokenizer.Match(__R('<'), 1)
|| tokenizer.Match(__R('?'), 1))
&& (tokenizer.Match(__R('='), 2)
|| tokenizer.Match(__R('!'), 2))
)
{
res = LookAround();
}
else if (tokenizer.Match(__R('<'), 1)
&& (tokenizer.IsPosDigital(2)
|| tokenizer.Match(__R('$'), 2)))
{
res = BackTracedGroup();
Quantifier(res);
}
else if (tokenizer.Match(__R('<'), 1)
&& (tokenizer.IsPosDigital(2)
|| tokenizer.Match(__R('#'), 2)))
{
res = BackReference();
Quantifier(res);
}
else //只能通过左括号判断捕获列表
{
res = CapturedGroup();
Quantifier(res);
}
}
else if (tokenizer.Match(__R('[')))
{
if (tokenizer.Match(__R('^'), 1))
{
res = NoSelection();
Quantifier(res);
}
else
{
res = Selection();
Quantifier(res);
}
}
else if (tokenizer.Finish())
{
return nullptr;
}
else if (!tokenizer.IsPosSpecial())
{
ReCharExprNode* tmp = nullptr;
Char(tmp);
res = tmp;
Quantifier(res);
}
else
{
return nullptr;
}
return res;
}