Convert Swift string to array

It is even easier in Swift:

let string : String = "Hello 🐶🐮 🇩🇪"
let characters = Array(string)
println(characters)
// [H, e, l, l, o,  , 🐶, 🐮,  , 🇩🇪]

This uses the facts that

• an Array can be created from a SequenceType, and
• String conforms to the SequenceType protocol, and its sequence generator
  enumerates the characters.

And since Swift strings have full support for Unicode, this works even with characters
outside of the “Basic Multilingual Plane” (such as 🐶) and with extended grapheme
clusters (such as 🇩🇪, which is actually composed of two Unicode scalars).

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Update: As of Swift 2, String does no longer conform to
SequenceType, but the characters property provides a sequence of the
Unicode characters:

let string = "Hello 🐶🐮 🇩🇪"
let characters = Array(string.characters)
print(characters)

This works in Swift 3 as well.

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Update: As of Swift 4, String is (again) a collection of its
Characters:

let string = "Hello 🐶🐮 🇩🇪"
let characters = Array(string)
print(characters)
// ["H", "e", "l", "l", "o", " ", "🐶", "🐮", " ", "🇩🇪"]