cpp-peglib/example/enter_leave.cc

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2023-03-25 12:42:56 +00:00
//
// enter_leave.cc
//
// Copyright (c) 2023 Yuji Hirose. All rights reserved.
// MIT License
//
#include <cstdlib>
#include <iostream>
#include <peglib.h>
using namespace peg;
int main(void) {
parser parser(R"(
S <- A+
A <- 'A'
)");
parser["A"].enter = [](const Context & /*c*/, const char * /*s*/,
size_t /*n*/, std::any & /*dt*/) {
std::cout << "enter" << std::endl;
};
parser["A"] = [](const SemanticValues & /*vs*/, std::any & /*dt*/) {
std::cout << "action!" << std::endl;
};
parser["A"].leave = [](const Context & /*c*/, const char * /*s*/,
size_t /*n*/, size_t /*matchlen*/,
std::any & /*value*/, std::any & /*dt*/) {
std::cout << "leave" << std::endl;
};
if (parser.parse("A")) { return 0; }
std::cout << "syntax error..." << std::endl;
return -1;
}