lambda express 사용하기 ][ captures

lambda express 사용하기 ][ captures

test해보기 : https://wandbox.org/permlink/fWfHGJXzDpMEBzjX

■  the basic syntax

[&] : capture by reference , all automatic storage duration variable declared in th reaching scope

[=] : capture by value, a value is copied

[x,&y] : capture x by value and y by a reference explicitly

view raw the basic syntax.md hosted with ❤ by GitHub

■ 컴파일 및 실행해보기

	//
	//
	// g++ prog.cc -Wall -Wextra -I/opt/wandbox/boost-1.69.0/gcc-8.3.0/include -std=c++17
	//
	//
	#include <iostream>
	#include <algorithm>
	#include <vector>
	using namespace std;
	int main() {
	int x = 1, y = 1;
	std::cout << x << " " << y << std::endl;
	auto func1 = [&x, &y]() { cout << ++x << " " << ++y << endl; };
	func1();
	auto func2 = [=]() mutable{ cout << ++x << " " << endl; };
	func2();
	auto func3 = [&]() mutable{ cout << ++x << " " << endl; };
	func3();
	auto func4 = [x, &y]()mutable { cout << ++x << " " << ++y << endl; };
	func4();
	}

view raw Captures.cpp hosted with ❤ by GitHub