scala 将多个函数调用参数合并为一个元组——这可以禁用吗? [英] scala coalesces multiple function call parameters into a Tuple -- can this be disabled?

问题描述

这在我的项目中违反了类型安全，因此我正在寻找一种方法来禁用它.似乎如果一个函数采用 AnyRef(或 java.lang.Object)，您可以使用任何参数组合调用该函数，Scala 会将参数合并为一个 Tuple 对象并调用该函数.

This is a troublesome violation of type safety in my project, so I'm looking for a way to disable it. It seems that if a function takes an AnyRef (or a java.lang.Object), you can call the function with any combination of parameters, and Scala will coalesce the parameters into a Tuple object and invoke the function.

在我的情况下，该函数不需要元组，并且在运行时失败.我希望这种情况会在编译时被发现.

In my case the function isn't expecting a Tuple, and fails at runtime. I would expect this situation to be caught at compile time.

object WhyTuple {
 def main(args: Array[String]): Unit = {
  fooIt("foo", "bar")
 }
 def fooIt(o: AnyRef) {
  println(o.toString)
 }
}

输出:

(foo,bar)

推荐答案

这里根本没有隐式或 Predef —— 只是很好的老式编译器魔法.您可以在 类型检查器.我现在无法在规范中找到它.

No implicits or Predef at play here at all -- just good old fashioned compiler magic. You can find it in the type checker. I can't locate it in the spec right now.

如果你有足够的动力，你可以在编译器中添加一个 -X 选项来防止这种情况发生.

If you're motivated enough, you could add a -X option to the compiler prevent this.

或者，您可以避免编写接受 TupleN 超类型的 arity-1 方法.

Alternatively, you could avoid writing arity-1 methods that accept a supertype of TupleN.

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