Note that it would actually be (also changing to an array to make your abbreviation of the author's example make more sense): `if arr?.contains("a") == true {

Note that it would actually be (also changing to an array to make your abbreviation of the author's example make more sense): `if arr?.contains("a") == true { ... }` or `if arr?.contains("a") ?? false { ... }` or `if (arr ?? []).contains("a") { ... }` or `if let arr= arr, arr.contains("a") { ... }` or `if arr!= nil, arr!.contains("a") { ... }` Optional<Bool> will not automatically unwrap where Bool is expected (since the compiler would have to assume nil is falsey, which is the kind of mushy shenanigans Swift explicitly denies).