duplicates:

• SR-8764 IR SIL generation failed for applyWrapped function in Swift4 Xcode 10

Issue Description:

I'm doing my codebase migration. Stumbled upon SEG Fault in this piece of code.

I tried executing in Playgrounds and a single view app with this code in the view controller file. Both fails to compile.

@discardableResult public func applyWrapped<T, U>(function: Optional<(T) -> U>, to value: Optional<T>) -> Optional<U> {
    switch (function, value) {
    case (let .some(f), let .some(v)):
        return .some(f(v))
    case (.none, _):
        return .none
    case (_, .none):
        return .none
    }
}

Im running Xcode 10 and trying to compile with Swift4