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php为什么弄点号连接字符串？

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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。

回复内容：

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，
特立独行也没什么大不了的，

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