Releaseビルドのときに怒られるやつ.swift

extension SomeClass {
    #if DEBUG
    @available(*, deprecated, message: "Replace before releasing")
    static func waitingReplace<X>(_ x: X) -> X {
        return x
    }
    #else
    @inline(__always)
    @available(*, unavailable, message: "Replace before releasing")
    static func waitingReplace<X>(_: X) -> X {
        fatalError("Replace before releasing")
    }
    #endif
}