相关疑难解决方法(0)

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示例是函数内的变量声明:

global $$link;

什么$$意思？

我刚刚开始学习Ruby,我编写了一个生成一些数字的程序,并将它们分配给变量@ one,@ two,@ three等.然后用户可以通过输入它的名称来指定要更改的变量(例如一).然后我需要做'@ [valueofinout] = asd'之类的事情.我怎么会这样做,并且有更好的方式,因为我想的方式似乎被劝阻了？我发现了

x = "myvar"
myvar = "hi"
eval(x) -> "hi"

但我不完全理解为什么需要第二行.在我的情况下,我会使用类似的东西

@one = "21"
input = "one"
input = "@" + input
changeto = "22"
eval(input) -> changeto