Function visitAstNodes

lib/astutils.h:59–90

 */
template<class T, class TFunc, REQUIRES("T must be a Token class", std::is_convertible<T*, const Token*> )>
void visitAstNodes(T *ast, const TFunc &visitor)
{
    if (!ast)
        return;

    // the size of 8 was determined in tests to be sufficient to avoid excess allocations. also add 1 as a buffer.
    // we might need to increase that value in the future.
    SmallVector<T *, 8 + 1> tokens;
    T *tok = ast;
    do {
        const ChildrenToVisit c = visitor(tok);
        if (c == ChildrenToVisit::done)
            break;

        if (c == ChildrenToVisit::op2 || c == ChildrenToVisit::op1_and_op2) {
            T *t2 = tok->astOperand2();
            if (t2)
                tokens.push_back(t2);
        }
        if (c == ChildrenToVisit::op1 || c == ChildrenToVisit::op1_and_op2) {
            T *t1 = tok->astOperand1();
            if (t1)
                tokens.push_back(t1);
        }

        if (tokens.empty())
            break;

        tok = tokens.back();
        tokens.pop_back();
    } while (true);
}

template<class TFunc>
const Token* findAstNode(const Token* ast, const TFunc& pred)