//
// 3.2.function.wrap.cpp
// chapter 03 runtime enhancement
// modern c++ tutorial
//
// created by changkun at changkun.de
// https://github.com/changkun/modern-cpp-tutorial
//

#include <functional>
#include <iostream>

using foo = void(int); // function pointer
void functional(foo f) {
 f(1);
}

int foo2(int para) {
 return para;
}

int foo3(int a, int b, int c) {
 return 0;
}

int main() {

 auto f = [](int value) {
 std::cout << value << std::endl;
 };
 functional(f); // call by function pointer
 f(1); // call by lambda expression

 // std::function wraps a function that take int paremeter and returns int value
 std::function<int(int)> func = foo2;

 int important = 10;
 std::function<int(int)> func2 = [&](int value) -> int {
 return 1+value+important;
 };
 std::cout << func(10) << std::endl;
 std::cout << func2(10) << std::endl;

 // bind parameter 1, 2 on function foo, and use std::placeholders::_1 as placeholder
 // for the first parameter.
 auto bindFoo = std::bind(foo3, std::placeholders::_1, 1,2);
 // when call bindFoo, we only need one param left
 bindFoo(1);

 return 0;
}