允许```被转义的理由是什么？ [英] What is the rationale in allowing `?` to be escaped?

问题描述

从 2.13.2 / 3

双引号 code>和问号？可以表示为
本身或转义序列 \和 \？ [...]。

The double quote " and the question mark ?, can be represented as themselves or by the escape sequences \" and \? [...].

简单地说，如下：

char x = '\?'; //or '\"'
char y = '?';  //or '"'

$ b b

表示相同的字符。为什么要处理这两个（特别是？）不同于其他字符？

推荐答案

\提供单引号字符文字和双引号字符串文字之间的一致性（它们被定义为使用相同的转义序列，结果 \'和 \可以在两者中使用）。我稍微猜一猜，但我估计委员会只是想在每个中定义不同的转义序列太麻烦了，没有好处，可以说是轻微的损害。

\" gives consistency between single-quoted character literals and double-quoted string literals (they're defined to use the same escape sequences, as a result \' and \" can be used in both). I'm slightly guessing, but I reckon the committee just figured it was too much bother to define different escape sequences in each, for no benefit and arguably a slight detriment.

\？是为了避免三字母： ?? = 是三字母，？\\ ？= 不是。

\? is for avoiding trigraphs: ??= is a trigraph, ?\?= isn't.

这篇关于允许```被转义的理由是什么？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！