Swift

Module 1 – Swift — first steps

Page 2 of 3 · About 15 minutes per lesson, including practice.

Values and decisions

15-minute session: read for 3 minutes, trace for 3, experiment for 7, and complete the check for 2. Spend longer whenever you need.

A decision chooses which statements run. The policy here is “ready at 80 or higher.” Trace 85, 79, 80, and 81 before running each case. The comparison includes 80. A program that prints the right answer for 85 may still be wrong at the boundary. Add a separate check rejecting scores below 0 or above 100; rejection and needing practice mean different things.

let introduces an immutable binding and var a mutable one. Converting text with Int(raw) may produce nil. if let unwraps a present value without force-unwrapping missing data.

let score = 85
if score >= 80 { print("Ready") } else { print("Practice") }

Expected result: Ready

Practice and evidence

Keep three notes: your prediction, the actual result, and why they match or differ. The completion check grades understanding; the practice task builds skill.

Language reference

Example code on Agila Forge ↗