Working with String.Index

String-Index.swift

// working with String index

let str = "The Swift Programming Language"

// accessing the first character
print("the first character is \(str[str.startIndex])")

// accessing the last character
print("the last character is \(str[str.index(before: str.endIndex)])")

// access range of characters
let ninthCharacterIndex = str.index(str.startIndex, offsetBy: 8)
print("range of characters \(str[str.startIndex...ninthCharacterIndex])")