Member function as first class function

将成员函数作为first class function。

stackoverflow Class and std::async on class member in C++

NOTE: 演示了两种典型的写法

A

NOTE: std::async内部使用std::invoke，参见 Callable 章节；

do_rand_stf is a non-static member function and thus cannot be called without a class instance (the implicit this parameter.) Luckily, std::async handles its parameters like std::bind, and bind in turn can use std::mem_fn to turn a member function pointer into a functor that takes an explicit this parameter, so all you need to do is to pass this to the std::async invocation and use valid member function pointer syntax when passing the do_rand_stf:

auto hand=async(launch::async,&A::do_rand_stf,this,i,j);

There are other problems in the code, though. First off, you use std::cout and std::endl without #includeing <iostream>. More seriously, std::future is not copyable, only movable, so you cannot push_back the named object hand without using std::move. Alternatively, just pass the async result to push_back directly:

ran.push_back(async(launch::async,&A::do_rand_stf,this,i,j));

A

NOTE: 使用lambda

You can pass the this pointer to a new thread:

async([this]()
{
    Function(this);
});

reddit What is the proper way to pass a member function to std::async?

方式总结

使用std::function + lambda

参见std::function章节。

使用lambda

[this]
{
    this->member_function();
}

使用pointer to member function

参见Pointer-to-member-function。

使用std::mem_fn

使用ca llable std::invoke

就像 stackoverflow Class and std::async on class member in C++ # A 中所描述的方式；

TODO

stackexchange C++ member function wrapper for interfacing with C APIs

stackexchange Simple wrapper for member function pointers with known signature