duplicates:

• SR-6602 0.magnitude fails to compile

Issue Description:

1.create a playground in Xcode OR iPad

2. run this code:

import Foundation

let i : Int = 0

print(i.magnitude) // prints "0\n"

let ui : UInt = 0

print(ui.magnitude) // prints "0\n"

let o = 0.magnitude

3. see run-time error:

error: MyPlaygroundBook.playground:6:11: error: arithmetic operation '18446744073709551615 + 1' (on unsigned 64-bit integer type) results in an overflow

let o = 0.magnitude

       ^