blocks|key|3560602|text|我最初说“不，你不能”。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3560603|但我还是要说“不，你不应该”！|3560604|请改用/*+*/。|3560605|示例：|3560606|#include+<stdio.h>

int+main+()
{
++//+Begin+comment+\
+++++continue+comment?
++return+printf+("Hello+world!\n");
}|code-block|syntax|javascript|3560607|出于其他帖子中解释的原因，上面的内容进行了编译。但这是错误的：|3560608|3560609|"//“用于单行注释(对于嵌套注释，应该使用"/*+*/”，对于多行注释，在"\“继续行上使用”\“是在程序中注入奇怪的、难以调试的错误的好方法。|unordered-list-item|3560610|3560611|就像通过鼻子吃菜豆一样:即使你可以，你也可能不应该。|3560612|我的..。|3560613|entityMap^0|0|0|0|0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Z|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|10|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|11|8|@]|9|@]|A|$]]|$1|F|3|G|5|6|7|12|8|@]|9|@]|A|$]]|$1|H|3|I|5|J|7|13|8|@]|9|@]|A|$K|L]]|$1|M|3|N|5|6|7|14|8|@]|9|@]|A|$]]|$1|O|3|-4|5|6|7|15|8|@]|9|@]|A|$]]|$1|P|3|Q|5|R|7|16|8|@]|9|@]|A|$]]|$1|S|3|-4|5|6|7|17|8|@]|9|@]|A|$]]|$1|T|3|U|5|6|7|18|8|@]|9|@]|A|$]]|$1|V|3|W|5|6|7|19|8|@]|9|@]|A|$]]|$1|X|3|-4|5|6|7|1A|8|@]|9|@]|A|$]]]|Y|$]]

I originally said "No, you can't".

But I still say "No, you SHOULDN'T"!

Use /* */ instead.

EXAMPLE:

<pre><code>#include &lt;stdio.h&gt;

int main ()
{
 // Begin comment \
 continue comment?
 return printf ("Hello world!\n");
}
</code></pre>

The above compiles, for reasons explained in other posts. But it's WRONG:

<ul>
<li>"//" are INTENDED for single-line comments (you should use "/* */" for nested, and for multi-line comments</li>
<li>Relying on "\" continuation lines is a great way to inject weird, difficult to debug errors in your program.</li>
</ul>

Just like eating stringbeans through your nose: even if you CAN, you probably SHOULDN'T.

IMHO...

blocks|key|1303153|text|是。在转换过程中，由\终止的线路会与下一条线路拼接在一起。它发生在翻译的第二阶段，在注释删除之前，在预处理器有机会完成它的工作之前。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1303154|注释识别和删除是在阶段3进行的。因此，您可以使用\将//注释转换为看起来像多行注释的注释。这通常会欺骗大多数语法突出显示的源代码解析器。|1303155|预处理器在阶段4工作。|1303156|这意味着您几乎可以使用\“多行”任何东西，包括注释和预处理器指令|1303157|#\
d\
e\
f\
i\
n\
e+\
ABC+\
int+i

int+main()+{
A\
B\
C+=+5;
}|code-block|syntax|javascript|1303158|附注:请注意，终止\不会在拼接行中引入任何空格。在使用\功能编写多行注释时，应该考虑到这一点。例如，下面的注释|1303159|//+to\
get\
her|1303160|代表一个单词“在一起”，而不是三个单独的单词“得到她”。显然，在注释中不正确地使用\可能会严重混淆甚至扭曲注释的本意。|1303161|entityMap^0|A|1|0|O|1|Q|2|0|0|B|1|0|0|9|1|R|1|0|0|15|1|0^^$0|@$1|2|3|4|5|6|7|Y|8|@$9|Z|A|10|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|11|8|@$9|12|A|13|B|C]|$9|14|A|15|B|C]]|D|@]|E|$]]|$1|H|3|I|5|6|7|16|8|@]|D|@]|E|$]]|$1|J|3|K|5|6|7|17|8|@$9|18|A|19|B|C]]|D|@]|E|$]]|$1|L|3|M|5|N|7|1A|8|@]|D|@]|E|$O|P]]|$1|Q|3|R|5|6|7|1B|8|@$9|1C|A|1D|B|C]|$9|1E|A|1F|B|C]]|D|@]|E|$]]|$1|S|3|T|5|N|7|1G|8|@]|D|@]|E|$O|P]]|$1|U|3|V|5|6|7|1H|8|@$9|1I|A|1J|B|C]]|D|@]|E|$]]|$1|W|3|-4|5|6|7|1K|8|@]|D|@]|E|$]]]|X|$]]

Yes. Lines terminated by a <code>\</code> are spliced together with the next line very early in the process of translation. It happens at phase 2 of translation, before comment removal and before preprocessor has a chance to do its work.

Comment recognition and removal takes place at phase 3. For this reason you can turn a <code>//</code> comment into what looks like a multi-line comment by using the <code>\</code>. This usually fools most syntax-highlighting source code parsers.

Preprocessor works at phase 4. 

This all means that you can "multiline" virtually anything using the <code>\</code>, including comments and preprocessor directives

<pre><code>#\
d\
e\
f\
i\
n\
e \
ABC \
int i

int main() {
A\
B\
C = 5;
}
</code></pre>

P.S. Please note that the terminating <code>\</code> does not introduce any whitespace into the spliced line. This should be taking onto account when writing multi-line comments using the <code>\</code> feature. For example, the following comment

<pre><code>// to\
get\
her
</code></pre>

stands for the single word "together" and not for three separate words "to get her". Obviously, incorrect use of <code>\</code> in comments might drastically obfuscate and even distort their intended meaning.

blocks|key|2383855|text|这里有一个很好的理由不要这样做。下面的程序打印"This+will+prints“。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2383856|#include+<iostream>
int+main()
{
++++std::cout+<<+"This+"
++++//+A+comment+...+\+
++++<<+"will+appear"
++++//+Another+comment+...+\
++++<<+",+but+this+won't"
++++<<+std::endl;
}|code-block|syntax|javascript|2383857|为什么？因为第一个\后面跟着一个空格，所以它只是注释的一部分，而不是行拼接字符。由于不可见的尾随空格，程序的行为可能会悄悄地发生重大变化。|offset|length|style|CODE|2383858|不这样做的一个更好的理由是:即使使用-pedantic，g%2B%2B也会出错。当我使用g%2B%2B编译这个程序时，输出就是"+this+"；第一个\后面的空格被忽略了。在我看来，这是它应该如何工作的，但这不是语言标准所说的。(行拼接发生在翻译阶段2。我想有人可能会争辩说，尾随的空格可以在阶段1中删除，但我不相信这是一个有效的论点--我不知道gcc的作者是否真的提出了这个论点。)在任何情况下，Sun4.5.2和g%2B%2B+CC版本5.5都不一致。|2383859|如果需要多行注释，请使用/*+...+*/或在每行开头插入//。我更喜欢后者，因为它更容易分辨出给定行是注释的一部分。(实际上是多个单行注释。)任何像样的编辑器都应该让你不用为N行输入//+N次就能做到这一点。或者，如果您要注释掉一段代码，请使用#if+0+...+#endif。|2383860|entityMap^0|0|0|9|1|0|I|9|1V|1|0|C|9|T|2|2K|2|3F|G|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|U|8|@$I|V|J|W|K|L]]|9|@]|A|$]]|$1|M|3|N|5|6|7|X|8|@$I|Y|J|Z|K|L]|$I|10|J|11|K|L]]|9|@]|A|$]]|$1|O|3|P|5|6|7|12|8|@$I|13|J|14|K|L]|$I|15|J|16|K|L]|$I|17|J|18|K|L]|$I|19|J|1A|K|L]]|9|@]|A|$]]|$1|Q|3|-4|5|6|7|1B|8|@]|9|@]|A|$]]]|R|$]]

Here's an excellent reason not to do this. The following program prints "This will appear".

<pre><code>#include &lt;iostream&gt;
int main()
{
 std::cout &lt;&lt; "This "
 // A comment ... \ 
 &lt;&lt; "will appear"
 // Another comment ... \
 &lt;&lt; ", but this won't"
 &lt;&lt; std::endl;
}
</code></pre>

Why? Because the first <code>\</code> is followed by a blank, and so it's just part of the comment, not a line-splicing character. The program's behavior can quietly and significantly change due to invisible trailing white space.

An even better reason not to do this: g++ gets it wrong, even with <code>-pedantic</code>. When I compile this program using g++ the output is just "This"; the trailing white space after the first <code>\</code> is ignored. In my opinion this is how it should work, but it's not what the language standard says. (Line splicing happens in translation phase 2. I suppose one might argue that the trailing blanks could be deleted in phase 1, but I'm not convinced that that's a valid argument -- and I don't know whether the gcc authors have actually made that argument.) In any case, g++ 4.5.2 and Sun CC version 5.5 disagree with each other.

If you want multi-line comments, either use <code>/* ... */</code>, or insert a <code>//</code> at the beginning of each line. I prefer the latter, because it's much easier to tell that a given line is part of the comment. (Actually it's multiple single-line comments.) Any decent editor should let you do this without typing <code>//</code> N times for N lines. Or, if you're commenting out a block of code, use <code>#if 0 ... #endif</code>.

Can // style comments be continued to the next line by using a back slash, like multi-line macros? E.g.

<pre><code>// here is a comment \
 and this is more comments \
const char* x = "hello"; // this line of "code" is actually still a comment
int x = 5; // and now an actual line of code
</code></pre>

C++ Multi-line comments using backslash

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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//样式注释可以像多行宏一样使用反斜杠继续到下一行吗？例如。// here is a comment \   and this is more comments \const char* x = "hello";  // this line of "code" is actually still a commentin...

问使用反斜杠的C++多行注释
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