我从编译器得到的错误是赋值的左侧必须是变量。我的用例是深度复制,但并不是真正相关。
The error I get from the compiler is "The left hand side of an assignment must be a variable". My use case is deep copying, but is not really relevant.
在C ++中,可以分配给 * this 。
In C++, one can assign to *this.
问题不在于如何绕过这个的转让。这很简单,但是决定不让这个变量的背后有什么理由。
The question is not how to circumvent assignment to this. It's very simple, but rather what rationale is there behind the decision not to make this a variable.
是技术或概念的原因?
Are the reasons technical or conceptual?
我的猜测到目前为止 - 在随机方法中重建Object的可能性容易出错(概念性),但技术上可行。
My guess so far - the possibility of rebuilding an Object in a random method is error-prone (conceptual), but technically possible.
编辑请限制因为java规格如此说明的变体。我想知道决定的原因
EDIT Please restrain from variations of "because java specs say so". I would like to know the reason for the decision
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在C ++中,可以分配给 * this
是的,但你不能在C ++中做 this = something ,我实际上认为这与你所询问的内容更接近在Java方面这里。
Yes, but you can't do this = something in C++, which I actually believe is a closer match for what you're asking about on the Java side here.
[...]决定不做的理由是什么这个一个变量。
我想说清晰度/可读性。
I would say clarity / readability.
这个被选为保留字,可能因为它没有作为显式参数传递一种方法。使用它作为普通参数并能够为其重新赋值,会严重损害可读性。
this was chosen to be a reserved word, probably since it's not passed as an explicit argument to a method. Using it as an ordinary parameter and being able to reassign a new value to it, would mess up readability severely.
事实上,很多人认为你不应该改变因此,参数变量完全存在。
In fact, many people argue that you shouldn't change argument-variables at all, for this very reason.
原因是技术性的还是概念性的?
Are the reasons technical or conceptual?
我认为主要是概念性的。但是会出现一些技术怪癖。如果你可以将值重新分配给这个,你可以完全隐藏局部变量后面的实例变量。
Mostly conceptual I would presume. A few technical quirks would arise though. If you could reassign a value to this, you could completely hide instance variables behind local variables for example.
我的猜测到目前为止 - 以随机方法重建对象的可能性容易出错(概念性),但技术上可行。
My guess so far - the possibility of rebuilding an Object in a random method is error-prone (conceptual), but technically possible.
我不确定我是否完全理解这个陈述,但是,容易出错可能是决定将其作为关键字的主要原因不是变量。
I'm not sure I understand this statement fully, but yes, error prone is probably the primary reason behind the decision to make it a keyword and not a variable.
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为什么java中不允许赋值给'this'?
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