“AND"与“&&"作为运营商 [英] 'AND' vs '&&' as operator

问题描述

我有一个代码库，其中开发人员决定使用 AND 和 OR 而不是 && 和 ||.

I have a codebase where developers decided to use AND and OR instead of && and ||.

我知道运算符的优先级存在差异(&& 在 and 之前)，但是对于给定的框架(PrestaShop 准确地说)这显然不是原因.

I know that there is a difference in operators' precedence (&& goes before and), but with the given framework (PrestaShop to be precise) it is clearly not a reason.

你用的是哪个版本?and 是否比 && 更具可读性?还是没有区别?

Which version are you using? Is and more readable than &&? Or is there no difference?

推荐答案

如果你使用 AND 和 OR，你最终会被这样的事情绊倒:

If you use AND and OR, you'll eventually get tripped up by something like this:

$this_one = true;
$that = false;

$truthiness = $this_one and $that;

想猜猜 $truthiness 等于什么?

如果你说false... bzzzt，对不起，错了！

If you said false... bzzzt, sorry, wrong!

$truthiness 上面的值是 true.为什么?= 具有比 更高的优先级 和.添加括号以显示隐式顺序使这一点更加清晰:

$truthiness above has the value true. Why? = has a higher precedence than and. The addition of parentheses to show the implicit order makes this clearer:

($truthiness = $this_one) and $that

如果您在第一个代码示例中使用 && 而不是 and，它会按预期工作并且是 false.

If you used && instead of and in the first code example, it would work as expected and be false.

正如在下面的评论中所讨论的，这也适用于获得正确的值，因为括号的优先级高于 =:

As discussed in the comments below, this also works to get the correct value, as parentheses have higher precedence than =:

$truthiness = ($this_one and $that)

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