test/decl/protocol/conforms/operator.swift

// RUN: %target-typecheck-verify-swift

protocol P0 {
  static func << (lhs: Self, rhs: Self) -> Self
}

// Satisfy operator requirement with a global function.
struct S0a : P0 { } 
func <<(lhs: S0a, rhs: S0a) -> S0a { return lhs }

// Satisfy operator requirement with a static method.
struct S0b : P0 { 
  static func <<(lhs: S0b, rhs: S0b) -> S0b { return lhs }
}

// Satisfy operator requirement with a static method in a generic struct.
struct S0c<T> : P0 {
  static func <<(lhs: S0c<T>, rhs: S0c<T>) -> S0c<T> { return lhs }
}