用“var {args}”初始化C ++ 0x的一个新功能，还是仅仅是语法糖？ [英] Is initializing with "var{args}" a new feature of C++0x, or merely syntactic sugar?

问题描述

我在阅读 C ++ 0x faq ，遇到了详细介绍初始化列表的部分。示例主要是以下变体：

I was reading the C++0x faq and came across the section detailing initializer lists. The examples were mostly variations of:

vector<int> vi = { 1, 2, 3 };
vector<int> vj({1, 2, 3});
// etc.

但是，列出的还是以下形式：

However, also listed was the form:

vector<int> vk{2};

这种形式出现在常见问题的其他地方，我很好奇它是否在语义上与初始两种形式，或只是语法糖为 vk（{x，y，z}）。

This form appears elsewhere in the faq, and I am curious as to whether it is semantically different from the initial two forms, or just syntactic sugar for vk({x, y, z}).

推荐答案

一种是统一初始化，另一种是初始化列表。它们是两个不同的东西，虽然你可以看到，它们可以产生类似的语法。

One is uniform initialization, and the other is initializer lists. They are two different things, although as you can see, they can produce similar syntax.

vector<int> vk{2};

是一个统一的初始化 - 其他两个是初始化列表。

is a uniform initialization- the other two are initializer lists.

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