如何两个字符串文字的串联工作？ [英] How does concatenation of two string literals work?

问题描述

char* a="dsa" "qwe";
printf("%s",a);

输出：dsaqwe

output: dsaqwe

我的问题是，为什么做这件事的工作。如果我给在两者之间字符串的空间或没有它地连接了字符串。​​

My question is why does this thing work. If I give a space or nothing in between two string literals it concatenates the string literals.

这是如何工作？

推荐答案

它是由ISO C标准定义的，相邻的字符串组合成一个。

It's defined by the ISO C standard, adjacent string literals are combined into a single one.

语言是有点干燥（这是一个标准的毕竟），但部分 6.4.5字符串字面 C11的规定：

The language is a little dry (it is a standard after all) but section 6.4.5 String literals of C11 states:

在翻译阶段6，由任何序列指定的多字节字符序列
  相邻的性格和identically- prefixed宽字符串文字令牌连接成
  一个多字节字符序列。

In translation phase 6, the multibyte character sequences specified by any sequence of adjacent character and identically-prefixed wide string literal tokens are concatenated into a single multibyte character sequence.

这也是在提到5.1.1.2转换阶段，6点，多了几分简洁：

This is also mentioned in 5.1.1.2 Translation phases, point 6, a little more succinctly:

相邻字符串文字令牌连接起来。

Adjacent string literal tokens are concatenated.

这基本上意味着ABC，高清是没有区别ABCDEF。

This basically means that "abc" "def" is no different to "abcdef".

这是通常用于制作长字符串同时还具有不错的格式化有用：

It's often useful for making long strings while still having nice formatting:

char *myString = "This is a really long "
                 "string and I don't want "
                 "to make my lines in the "
                 "editor too long, because "
                 "I'm basically anal retentive :-)";

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