Swift 2 String Algorithms - http://sketchytech.blogspot.com/2014/08/swift-pure-swift-method-for-returning.html

StringAlgorithms.swift

var str = "Hello Swift!"
var aStr = "Hello World!"

str.startIndex // first index
str.endIndex // end index

str.startIndex.distanceTo(str.endIndex) // string length
str.characters.count // string length

str[str.startIndex.advancedBy(4)] // get character at index 4
str[str.startIndex.advancedBy(4)...str.startIndex.advancedBy(8)] // get characters in range index 4 to 8

str.characters.last // retrieve last letter
str.characters.first // retrieve first letter

str.removeAtIndex(str.characters.indices.first!) // remove first letter
str.removeAtIndex(str.characters.indices.last!) // remove last letter

let first = str.characters.dropFirst()
String(first) // dropFirst

let last = str.characters.dropLast()
String(last) // dropLast

"aeiou".characters.contains("a") // contains character
str.characters.filter{!"aeiou".characters.contains($0)} // remove vowels

str.characters.indices // retrieve the Range value for string

str.isEmpty // test whether there is anything in the string

str.startIndex.advancedBy(5) // advance index
str.substringToIndex(str.startIndex.advancedBy(5)) // returns string up to the 5th character
str.substringFromIndex(str.startIndex.advancedBy(5)) // returns string from the 5th character

min("antelope","ant") // returns the alphabetical first
max("antelope","ant") // returns the alphabetical last

str.characters.prefix(5) // returns first 5 characters
str.characters.reverse() // return reverse array of Characters

str.characters.suffix(5) // returns last 5 characters
swap(&str, &aStr) // swaps two strings for the value of one another