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Home Backend Development PHP Tutorial php为什么弄点号连接字符串?

php为什么弄点号连接字符串?

Jun 17, 2016 am 08:31 AM

我知道的大部分语言都是加号来连接字符串的。

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对于像PHP、JS、Python 这种弱类型来说,+既是数字的相加,也是字符串的连接,问题来了:JS中 var a = 1+1; var a="1"+1; var a = "1"+"1"; 这些结果a是多少?是2还是11?你可能要花几分钟去思考或查资料。
但PHP不用思考就知道全都是1+1=2啊这么简单,因为PHP里面点号才是字符串连接。
再问一个为什么JS不能设计成用点号作字符串连接?因为对象。JS里面是用点号调用对象属性和方法,用同一个就会矛盾。PHP里面用横线箭头,看似很蠢,实则避免了各种混乱,大智若愚啊。 为什么Python在新建实例的时候不用new 呢?

为什么C++在声明字符串的时候不能用单引号呢?

为什么JAVA要用import而不用include呢?

为什么object C不用interface呢?

为什么C++的继承要用:不用extends呢?

为什么要问这种问题呢? php 的点连接字符串和美元符号变量声明来自于 perl。

而在 php 出现之前,绝大部分 web cgi 程序不是直接用 c 就是用 perl 写的。 php是世界上最好的语言,
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