Optional transformed capture has incorrect type when nil #827

let pattern = Regex {
    Capture(OneOrMore(.digit)) { Int($0)! }
    Optionally {
        "."
        Capture(OneOrMore(.digit)) { Int($0)! }
    } 
}

for str in ["123.456", "789"] {
    if let match = str.wholeMatch(of: pattern) {
        print(match.output)
        let erasedMatch = Regex<AnyRegexOutput>.Match(match)
        print(erasedMatch[1].type, erasedMatch[2].type)
    }
}

// Output:
// ("123.456", 123, Optional(456))
// Int Optional<Int>
// ("789", 789, nil)
// Int Optional<Substring>