do-while循环的范围？ [英] Scope of do-while loop?

问题描述

在Java中， do-while 循环的主体和循环条件不属于同一范围。因此以下代码将无法编译：

In Java, the body of a do-while loop and the loop condition do not belong to the same scope. So the following code won't compile:

do {
    boolean b = false;
} while (b); // b cannot be resolved to a variable

但这段代码对我有用。

此外，如果身体和状况在同一范围内，我找不到任何陷阱;因为正文总是被执行，而Java没有转到，我不知道最外面的中的变量声明怎么做 - 而可以跳过正文范围。即使有可能，编译器也总能检测到这种可能性，然后产生编译时错误。

Also, I cannot find any pitfalls if the body and the condition are in the same scope; since the body will always get executed, and Java does not have Goto, I don't know how a variable declaration in the outermost do-while body scope could be skipped. Even if it is possible, the compiler could always detect such possibility and then produce compile time errors.

这种行为是否有任何原因（除了保留<$ c） $ c> do-while 以与相同的格式循环，而）？我很好奇。感谢您的任何输入！

Is there any reason for this behavior (aside from keeping the do-while loop in the same format as while)? I am really curious. Thanks for any inputs!

推荐答案

因为这是Java中定义范围的方式;在 {} 里面是一个新的范围。

Because that's how scope is defined in Java; inside {} is a new scope.

IMO对特殊情况单一的情况没有多大意义建造。

IMO it wouldn't make much sense to special-case a single construct.

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