C ++ 0x“从”容器 [英] C++0x "move from" container

问题描述

在C ++ 0x中，我们通过 std :: move 获得了有关容器的效率提升：

In C++0x, we get an efficiency boost concerning containers with std::move:

SomeExpensiveType x = /* ... */;
vec.push_back(std::move(x));

但我找不到任何其他方式。我的意思是这样：

But I can't find anything going the other way. What I mean is something like this:

SomeExpensiveType x = vec.back(); // copy!
vec.pop_back(); // argh

这在适配器的 stack 。可能有这样的存在：

This is more frequent (the copy-pop) on adapter's like stack. Could something like this exist:

SomeExpensiveType x = vec.move_back(); // move and pop

避免复制？这是否已经存在？我在n3000找不到类似的东西。

To avoid a copy? And does this already exist? I couldn't find anything like that in n3000.

我有一种感觉，我错过了一些显而易见的东西（像它的不必要的东西），所以我准备ru dum。 ：3

I have a feeling I'm missing something painfully obvious (like the needlessness of it), so I am prepared for "ru dum". :3

推荐答案

我可能完全错了，但不是你想要的

I might be total wrong here, but isn't what you want just

SomeExpensiveType x = std::move( vec.back() ); vec.pop_back();

假设SomeExpensiveType有一个移动构造函数。 （显然对你的情况）

Assuming SomeExpensiveType has a move constructor. (and obviously true for your case)

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