scala coalesces multiple function call parameters into a Tuple — can this be disabled?

Question

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), y

Answer 1

Edit: According to people better informed than me, the following answer is actually wrong: see this answer. Thanks Aaron Novstrup for pointing this out.

This is actually a quirk of the parser, not of the type system or the compiler. Scala allows zero- or one-arg functions to be invoked without parentheses, but not functions with more than one argument. So as Fred Haslam says, what you've written isn't an invocation with two arguments, it's an invocation with one tuple-valued argument. However, if the method did take two arguments, the invocation would be a two-arg invocation. It seems like the meaning of the code affects how it parses (which is a bit suckful).

As for what you can actually do about this, that's tricky. If the method really did require two arguments, this problem would go away (i.e. if someone then mistakenly tried to call it with one argument or with three, they'd get a compile error as you expect). Don't suppose there's some extra parameter you've been putting off adding to that method? :)