protocol SomeProtocol {
    typealias Member = StaticMember<Self>
}

struct A: SomeProtocol {
    let name: String
}

extension StaticMember where Base: SomeProtocol {
    static var foo: A.Member { .init(A(name: "foo")) } // ok
    static var baz: A.Member { .init(.init(name: "baz")) } // ok
    static var bar: A.Member { StaticMember<A>(A(name: "bar")) } // ok
    static var bat: A.Member { StaticMember(A(name: "bat"))} // error: 'A' is not convertible to 'Base'
    static var boo: A.Member { StaticMember(.init(name: "boo")) } // error: Type of expression is ambiguous without more context
}