Loops — for-in, while, repeat-while
Learn how to repeat tasks with for-in , while , and repeat-while loops.
Loops — for-in, while, repeat-while is a free Swift Academy lesson on CoddyKit — lesson 3 of 3. You can read the complete lesson below for free — then practise it hands-on in the browser with a built-in code editor and a 24/7 AI tutor. It is part of the Swift Academy learning path, one of 3 lessons in the course, and your progress syncs across the web and the CoddyKit app.
Intro
Loops repeat code. Swift provides for-in, while, and repeat-while.
for-in loop
for-in iterates over ranges, arrays, or any sequence.
for i in 1...3 {
print("i =", i)
}while loop
while repeats as long as the condition is true, checking before each run.
var n = 3
while n > 0 {
print("n =", n)
n -= 1
}repeat-while loop
repeat-while checks the condition after running the body, so it always runs at least once.
var count = 0
repeat {
print("count =", count)
count += 1
} while count < 3break & continue
Use continue to skip, break to exit a loop early.
for i in 1...5 {
if i == 3 { continue } // skip 3
if i == 4 { break } // stop loop
print("i =", i)
}Tips
Tips:
- Prefer for-in for known sequences.
- Use while for unknown counts.
- Use repeat-while when the body must run at least once.
Loop guarantee
Quick check: Which loop guarantees the body runs at least once?
Recap
Recap: Use for-in for sequences, while for unknown repeats, repeat-while to run at least once.
Frequently asked questions
Is the “Loops — for-in, while, repeat-while” lesson free?
Yes — the full text of “Loops — for-in, while, repeat-while” is free to read here on the web, and the Swift Academy course includes 3 lessons in total. To practise it interactively (a built-in code editor and a 24/7 AI tutor) and unlock the rest of the Swift Academy course, upgrade to CoddyKit PRO.
What will I learn in “Loops — for-in, while, repeat-while”?
Learn how to repeat tasks with for-in , while , and repeat-while loops. You practise Swift Academy with hands-on code you run directly in the browser, and a 24/7 AI tutor answers your questions as you work through the lesson.
Do I need any experience to start Swift Academy?
No prior experience is required. Swift Academy on CoddyKit is structured for beginners through advanced learners; this is — lesson 3 of 3, so you can start here or from the beginning and move at your own pace.
How long does the “Loops — for-in, while, repeat-while” lesson take?
Most CoddyKit lessons take about 5–10 minutes. Each one is bite-sized and interactive, so you make steady progress and pick up exactly where you left off across the web and the app.
Can I write and run code in this Swift Academy lesson?
Yes. Every Swift Academy lesson includes a built-in code editor, so you write and run real code right in your browser and get instant AI feedback — no local setup required.
All lessons in this course
- if/else basics
- switch — exhaustiveness, ranges, tuples, where
- Loops — for-in, while, repeat-while