Function llama_grammar_accept

llama.cpp:7959–7985

takes a set of possible pushdown stacks on a grammar, which are required to be positioned at a character range (see `llama_grammar_advance_stack`), and produces the N possible stacks if the given char is accepted at those positions

// produces the N possible stacks if the given char is accepted at those
// positions
static std::vector<std::vector<const llama_grammar_element *>> llama_grammar_accept(
        const std::vector<std::vector<llama_grammar_element>>         & rules,
        const std::vector<std::vector<const llama_grammar_element *>> & stacks,
        const uint32_t                                                  chr) {

    std::vector<std::vector<const llama_grammar_element *>> new_stacks;

    for (const auto & stack : stacks) {
        if (stack.empty()) {
            continue;
        }

        auto match = llama_grammar_match_char(stack.back(), chr);
        if (match.first) {
            const llama_grammar_element * pos = match.second;

            // update top of stack to next element, if any
            std::vector<const llama_grammar_element *> new_stack(stack.begin(), stack.end() - 1);
            if (!llama_grammar_is_end_of_sequence(pos)) {
                new_stack.push_back(pos);
            }
            llama_grammar_advance_stack(rules, new_stack, new_stacks);
        }
    }

    return new_stacks;
}

static std::vector<llama_grammar_candidate> llama_grammar_reject_candidates(
        const std::vector<std::vector<llama_grammar_element>>         & rules,