String indices in Swift 2

In a Playground, if you go to menu View > Debug Area > Show debug area, you can see the full error in the console:

/var/folders/2q/1tmskxd92m94__097w5kgxbr0000gn/T/./lldb/94138/playground29.swift:5:14: error: 'indices' is unavailable: access the 'indices' property on the collection for index in indices(greeting)

Also, Strings do not conform to SequenceTypes anymore, but you can access their elements by calling characters.

So the solution for Swift 2 is to do it like this:

let greeting = "Guten Tag"

for index in greeting.characters.indices {
    print(greeting[index])
}

Result:

G
u
t
e
n

T
a
g

Of course, I assume your example is just to test indices, but otherwise you could just do:

for letter in greeting.characters {
    print(letter)
}