指定合同违规处理程序 [英] Specifying a violation handler for contracts

问题描述

在C ++中支持基于合同的编程b $ b 在Rapperswil的C ++ 20工作草案中被采用。此语言功能的一部分是违反处理程序的概念，当违反合同时将调用该处理程序。

Support for contract based programming in C++ was adopted ino the C++20 working draft in Rapperswil. One part of this language feature is this notion of a violation handler which will be invoked when a contract is violated.

草药萨特的旅行报告指出：

您可以安装自己的违规处理程序并进行运输

You get to install your own violation handler and ship a release build with the option of turning on enforcement at run time.

但是 [dcl.attr.contract] 说：

程序的违规处理程序是 noexcept _opt $ b类型的函数$ b函数（对 const std :: contract_violation 的左值引用）返回 void ，并在实现定义的方式。 [...]不应采用编程方式来设置或修改违规处理程序。它是由实现定义的，它是如何为程序建立违规处理程序的，以及如何设置 std :: contract_violation （[support.contract.cviol]）参数的值，

The violation handler of a program is a function of type "noexcept_opt function of (lvalue reference to const std​::​contract_­violation) returning void", and is specified in an implementation-defined manner. [...] There should be no programmatic way of setting or modifying the violation handler. It is implementation-defined how the violation handler is established for a program and how the std​::​contract_­violation ([support.contract.cviol]) argument value is set, except as specified below.

这对我来说还是很不清楚的。实现如何允许我以非编程方式设置自己的违规处理程序？我必须在gcc，clang和msvc上做什么？

This is very unclear to me. How might an implementation allow me to set my own violation handler, in a non-programmatic way? What will I have to do on gcc, clang, and msvc?

推荐答案

在非编程方式中，实现如何允许我设置自己的违规处理程序

How might an implementation allow me to set my own violation handler, in a non-programmatic way?

这是要确定的实现，但我宁愿怀疑这将是某种命令行参数。您将命名一个函数，编译器/链接器将使它成为违规处理程序。否则，他们可能会选择您要实现的某些特定函数名称。

That's for implementations to determine, but I rather suspect it would be a command line parameter of some sort. You'd name a function, and the compiler/linker would make that the violation handler. And if not that, then they would probably pick some specific function name that you implement.

此处的要点是，所使用的函数是 static >，从C ++抽象模型的角度来看。当编译器启动时，它确切地知道将调用哪个函数，就像系统对 main 的调用以及处理<$ c的程序部分一样$ c> main 的返回值。

The point here is that the function being used is static, from the perspective of the C++ abstract model. When the compiler starts, it knows exactly which function will be called, much like the call by the system to main, as well as the part of the program that handles main's return values.

这篇关于指定合同违规处理程序的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！