有没有在PHP裸字符串的合法使用？ [英] Is there any legitimate use for bare strings in PHP?

问题描述

这个问题让我想起了光秃秃的字符串。

This question got me thinking about bare strings.

当PHP看到，这不是用引号括起来的字符串，它首先检查，看它是否是一个常数。如果不是，它只是假定它是一个字符串，反正下去。因此，举例来说，如果我有

When PHP sees a string that's not enclosed in quotes, it first checks to see if it's a constant. If not, it just assumes it's a string and goes on anyway. So for example if I have

echo $foo[bar];

如果有它使用的数组键恒定叫吧，但如果不是那么它把酒吧作为一个字符串裸露，所以它的行为就像

If there's a constant called bar it uses that for the array key, but if not then it treats bar as a bare string, so it behaves just like

echo $foo["bar"];

这可引起各种问题，如果在未来的某个时间加入具有相同名称的恒定

This can cause all kinds of problems if at some future date a constant is added with the same name.

我的问题是，有没有在它实际上是有意义的使用裸字符串的任何情况吗？

My question is, is there any situation in which it actually makes sense to use a bare string?

推荐答案

不，我不能看到一个实例，其中是明智的，它总是很危险。使用字符串不含引号绝对应该保留，以解决常数。我不明白怎么PHP的发明者可以决定在所有介绍的这款可笑的行为 - 它使正确使用常量几乎是不可能的（因为如果你试图访问一个尚未定义的常量，PHP会悄悄地和愚蠢地产生字符串）不给的任何的好处。

Nope, I can not see a single instance where it would make sense, and it always is dangerous. Using strings without quotes should absolutely be reserved to address constants. I don't understand how the inventors of PHP could decide to introduce this ridiculous behaviour at all - it makes the proper use of constants almost impossible (because if you try to access a constant that has not been defined, PHP will silently and stupidly generate a string) without giving any benefit.

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