Swiftly

Swift 5.1 references for busy coders

Range operator (1...5)

Range operators is a shortcuts for expressing a range of values.

Closed range a...b

for i in 1...4 {
  print(i)
}
// 1
// 2
// 3
// 4

Half-open range a..<b

for i in 1..<4 {
  print(i)
}
// 1
// 2
// 3

Half-open range used on an array

let players = ["Ayesha", "Beatrix", "Chris", "Daisy"]
for i in 0..<players.count {
  print("Player \(i + 1) is \(players[i])")
}
// Player 1 is Ayesha
// Player 2 is Beatrix
// Player 3 is Chris
// Player 4 is Daisy

One-sided-ranges [a...] and [...a]

let players = ["Ayesha", "Beatrix", "Chris", "Daisy"]
print(players[2...]) // ["Chris", "Daisy"]
print(players[...2]) // ["Ayesha", "Beatrix", "Chris"]
print(players[..<2]) // ["Ayesha", "Beatrix"]