error: invalid redeclaration of 'protocolFunc()' #CodePiece #cswift

CodePiece.swift

protocol A {
    func protocolFunc ();
}

protocol B {
    func protocolFunc ();
}

struct Sample {
}

extension Sample: A {
    func protocolFunc() {
        print("extension A")
    }
}

extension Sample: B {
    func protocolFunc() {
        print("extension B")
    }
}

let a = Sample()
a.protocolFunc()