英文:
In Java, can you change/set the value of the variable in a for loop?
问题
抱歉，如果我的术语不正确的话。
在Java中，如果我有一个类似以下形式的for循环：
Entry something_else = ....;
for (Entry x : entries) {
x = something_else;
}
在上述for循环的循环体内将循环变量（x）设置为something_else是否合适/可以接受？
英文:
My apologies in advance if my terminology is incorrect.
In Java, if I have a for loop of the form:
Entry something_else = ....;
for (Entry x : entries) {
x = something_else;
}
is it kosher/ok to set that loop variable (x) to something_else inside the body of the for loop as above?
答案1
得分: 1
这段代码绝对等同于：
Entry something_else = ....;
for (Entry y : entries) {
Entry x = y; // 对该对象引用的复制
x = something_else; // 对 y 毫无影响
}
除此之外，它是有效的。
因此，这段代码可能会产生一些令人“惊讶”的效果，这可能不是作者的本意。
英文:
This code is absolutely equivalent to:
Entry something_else = ....;
for (Entry y : entries) {
Entry x = y; // a copy of the reference to that object
x = something_else; // has no effect whatsoever on y
}
Otherwise, it works.
So this code may do something surprising, which may not be what the author meant.
答案2
得分: 0
是的，这是可能的，但不是一个好主意。
更有意义的做法是创建另一个变量并赋予它新的期望值，从而消除任何可能的混淆。
我想不出有哪种情况下这样做会增加清晰度或任何其他好处。也许你有一个例子呢？
英文:
Yes, it is possible, but not a good idea.
It makes much more sense to just create another variable and give it the newly desired value, eliminating any possible confusion.
I can't think of a scenario where doing this adds clarity or any other benefit. Maybe you have an example?
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