Conditionals
if/else if/else work as usual
— no parentheses needed around the condition, unlike most other
C-family languages in this tutorial.
Example: a time-of-day greeting
let hour = 14
let greeting: String
if hour < 12 {
greeting = "Good morning"
} else if hour < 18 {
greeting = "Good afternoon"
} else {
greeting = "Good evening"
}
print(greeting)
Good afternoon
Swift's switch is also commonly used for multi-way
branches, and unlike some languages, it doesn't silently fall through to
the next case by default — each case is self-contained, which avoids a
classic C/Java bug where a forgotten break lets execution
accidentally continue into the next case.
let hour = 14
let greeting: String
if hour < 12 {
greeting = "Good morning"
} else if hour < 18 {
greeting = "Good afternoon"
} else {
greeting = "Good evening"
}
print(greeting)
Good afternoon