Why isn't operator overloading working in REPL?

Using Swift
1

I'm trying to define the + operator for a V type I defined for this test. Here is what I'm entering in the REPL, on my MacBook Pro:

1> struct V {
  2.     var x: Int, y: Int
  3. }
  4.
  4> extension V {
  5.     static func + (left: V, right: V) -> V {
  6.         return V(x: left.x + right.x, y: left.y + right.y)
  7.     }
  8. }
  9> let a = V(x: 1, y: 2)
a: V = {
  x = 1
  y = 2
}
 10> let b = V(x: 3, y: 4)
b: V = {
  x = 3
  y = 4
}
 11> let c = a + b
error: repl.swift:11:11: error: binary operator '+' cannot be applied to two 'V' operands
let c = a + b
        ~ ^ ~

repl.swift:11:11: note: overloads for '+' exist with these partially matching parameter lists: 
(Float, Float), (Double, Double), (Float80, Float80), (UInt8, UInt8), (Int8, Int8),
(UInt16, UInt16), (Int16, Int16), (UInt32, UInt32), (Int32, Int32), (UInt64, UInt64),
(Int64, Int64), (UInt, UInt), (Int, Int), (String, String), (C, S), (S, C), (RRC1, RRC2),
(Self, Self.Stride), (Self.Stride, Self), (UnsafeMutablePointer<Pointee>, Int),
(Int, UnsafeMutablePointer<Pointee>), (UnsafePointer<Pointee>, Int), 
(Int,UnsafePointer<Pointee>)
let c = a + b
          ^

Did I write anything wrong? Is this a limitation with the REPL?

Thank you in advance for the help.

2

Try defining the operator in global scope.

Could be something related to it. This clearly doesn't happen in Xcode.

3

It works as written in an Xcode playground, so it sounds like a REPL problem. I see the same thing in the REPL on my end.

4

Thank you, guys, assigning it globally works:

func + (l: V, r: V) -> V {
    return V(x: l.x + r.x, y: l.y + r.y)
}

The original code compiles and works, however. So it is a REPL issue.