How to not break automatically in switch statements in Swift?

question swift
Ram Patra Published on October 22, 2023

In Swift, the switch statement doesn’t automatically fall through to the next case. Each case block is designed to execute only the code within that case, and it doesn’t continue to the next case unless you use the fallthrough keyword.

If you don’t want Swift to break automatically after each case and you want to intentionally allow fall-through behavior, you can use the fallthrough statement to explicitly specify this behavior. Here’s an example:

let number = 1

switch number {
case 1:
    print("It's one")
case 2:
    print("It's one or two")
    print("It's something else")

In this code, when number is 1, it will print both “It’s one” and “It’s one or two” because of the fallthrough statement.

If you don’t include fallthrough, Swift will execute only the code in the matching case and then exit the switch statement. So, by default, Swift breaks after each case, and you need to explicitly use fallthrough if you want to allow fall-through behavior. This is different to, let’s say, Java where you have to explicitly use break if you want to only execute code in the matching case.

Ram Patra Published on October 22, 2023
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