Swift 3.1.1だとエラーになります。

$ docker run --privileged -it --rm norionomura/swift:311 swift -I /usr/lib/swift/clang/include Welcome to Swift version 3.1.1 (swift-3.1.1-RELEASE). Type :help for assistance. 1> let data = (0..<2*3).map { UInt8($0) } 2. let a = data.map { $0 + 1 } 3. let b: [UInt8] = data.map { $0 + 1 } error: repl.swift:3:32: error: ambiguous use of operator '+' let b: [UInt8] = data.map { $0 + 1 } ^

(edited)