Five kinds of callable objects: Functions Pointers to functions Objects of a class that overloads () Objects created by bind Objects created by lamdba expressions 1-2. Functions and Pointers to functions bool range5to10(int val) // <-- bool (*p_func)…

We learned in 7.11 that there are "array-like" objects that are not true arrays but can be treated like arrays for most purposes. A similar situation exists for functions. A callable object is any object that can be invoked in a function invocat…

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PHP: Callback / Callable 类型 - Manual https://www.php.net/manual/zh/language.types.callable.php Callback / Callable 类型 自 PHP 5.4 起可用 callable 类型指定回调类型 callback.本文档基于同样理由使用 callback 类型信息. 一些函数如 call_user_func() 或 usort() 可以接受用户自定义的回调函数作为参数.回调函数不止可以是简单函…

1.constexpr变量:声明为constexpr的变量一定是一个常量,新标准允许定义一种特殊的constexpr函数使得编译时就可计算结果,这样就能用constexpr函数去初始化constexpr变量. 2.类型别名:1.typedef     2.using SI = Sales_item;  //SI是Sales_item的别名声明,把等号左侧的名字规定成等号右侧类型的别名 3.auto:auto让编译器通过初始值来推算变量类型.auto i = 0, *p = &i; //ok  …

Executors In all of the previous examples, there's a close connection between the task being done by a new thread, as defined by its Runnable object, and the thread itself, as defined by aThread object. This works well for small applications, but in…

The open source, cross platform, free C++ IDE. Code::Blocks is a free C++ IDE built to meet the most demanding needs of its users. It is designed to be very extensible and fully configurable. Finally, an IDE with all the features you need, having a c…

[C++11lambda表达式] mutable 修饰符,用于修改[]中以值传递的变量,无mutable修饰符的话则不行. 使用示例: #include <vector> #include <iostream> #include <algorithm> #include <functional> int main() { std::vector<,,,,,, }; ; c.erase(std::remove_if(c.begin(), c.end(),…

在 tornado 中异步无阻塞的执行耗时任务 在 linux 上 tornado 是基于 epoll 的事件驱动框架,在网络事件上是无阻塞的.但是因为 tornado 自身是单线程的,所以如果我们在某一个时刻执行了一个耗时的任务,那么就会阻塞在这里,无法响应其他的任务请求,这个和 tornado 的高性能服务器称号不符,所以我们要想办法把耗时的任务转换为不阻塞主线程,让耗时的任务不影响对其他请求的响应. 在 python 3.2 上,增加了一个并行库 concurrent.futures,这个…

Usually, when you develop a simple, concurrent-programming application in Java, you create some Runnable objects and then create the corresponding Thread objects to execute them. If you have to develop a program that runs a lot of concurrent tasks, t…