Issue Description:

func f() throws -> Int { 3 }
func g() throws {
    _ = 3 + try f() // error: 'try' cannot appear to the right of a non-assignment operator
   _ = 3 + (try f()) // OK
}

The diagnostic wording is not quite accurate. In the second line, the try is still on the right of a non-assignment operator and that's alright, it is not on the immediate right.

Maybe we should use "immediate right" instead? I'm not sure if that's too technical, maybe there's a better phrasing without sacrificing accuracy.

If we don't already, we could also provide a fix-it to add parens. (I didn't realize this is something you could do to fix the issue until today, normally I would hoist the try out to immediately follow the = to resolve this issue).