// d2mcpp: https://github.com/mcpp-community/d2mcpp

// license: Apache-2.0

// file: src/cpp11/tests/00-auto-and-decltype/4.cpp

//

// Exercise/练习: cpp11 | 00 - auto and decltype | 类/结构体成员类型推导

//

// Tips/提示: 区分 decltype(obj) 与 decltype((obj)), 带括号是表达式会推导出引用类型

//

// Docs/文档:

// - https://en.cppreference.com/w/cpp/language/auto

// - https://en.cppreference.com/w/cpp/language/decltype

// - https://github.com/mcpp-community/d2mcpp/blob/main/book/src/cpp11/00-auto-and-decltype.md

//

// 练习交流讨论: http://forum.d2learn.org/post/357

//

// Auto-Checker/自动检测命令:

//

// d2x checker auto-and-decltype-4

//

import std;

import d2x;

// 4. 类/结构体成员类型推导

struct Object {

const int a;

double b;

Object() : a(1), b(2.0) { }

};

int main() {

const Object obj;

bool type_check = false;

// obj的类型推导 和 (obj) 的类型推导

type_check = std::is_same<decltype(obj), const Object>::value;

d2x::check(type_check, "type_check"); type_check = false; // dont change this line

type_check = std::is_same<decltype((obj)), D2X_YOUR_ANSWER>::value;

d2x::check(type_check, "type_check"); type_check = false; // dont change this line

// obj.a的类型推导 和 (obj.a) 的类型推导

type_check = std::is_same<decltype(obj.a), D2X_YOUR_ANSWER>::value;

d2x::check(type_check, "type_check"); type_check = false; // dont change this line

type_check = std::is_same<decltype((obj.a)), D2X_YOUR_ANSWER>::value;

d2x::check(type_check, "type_check"); type_check = false; // dont change this line

// obj.b的类型推导 和 (obj.b) 的类型推导

type_check = std::is_same<decltype(obj.b), D2X_YOUR_ANSWER>::value;

d2x::check(type_check, "type_check"); type_check = false; // dont change this line

type_check = std::is_same<decltype((obj.b)), D2X_YOUR_ANSWER>::value;

d2x::check(type_check, "type_check"); type_check = false; // dont change this line

d2x::wait();

return 0;

}