1a_I_See_No_Nil.playground, optToString compiler warning

[Leglaw]

Using Swift 2.1,

let v = split(value) { $0 == "(" || $0 == ")" }

Compiler complains:
Cannot invoke 'split' with an argument list of type '(String, (String) -> Bool)'

[alskipp]

Since Swift 2, most functions have become methods. Also String is no longer a CollectionType which introduces further complication. The following works, but it involves a fair amount of work.

let value = "(one)(two)(three)"
let v = value.characters.split { $0 == "(" || $0 == ")" }
print(v.map(String.init)) // ["one", "two", "three"]

Incidentally the project has just been updated to Swift 2.1, so all Playgrounds should all work as expected now.