Open Radar

 
Summary:
The compiler gives an error ("extraneous argument label '<name>:' in subscript") when attempting to add to a class a subscripting setter where the first argument has no external name and is a tuple with a named member in position zero as a parameter.

Steps to Reproduce:
1. Create a class in Swift
2. Add a subscript
  a. that has a first parameter with no external name
  b. which is a tuple having a named zeroth member (e.g., `(a: Int, Int)`)
3. Notice the error when attempting to build (error does not show up inline in Xcode)

Expected Results:
Code builds and runs.

Actual Results:
Build error ("extraneous argument label '<name>:' in subscript").

Version:
Version 6.3.2 (6D2105)

Minimal Example:
class GetSet {
  subscript(position: (x: Int, y: Int)) -> Int {
    get { return 0 }
    set { }
  }
}