You want to assign a descriptive string to a variable based on an integer code using when as an expression. Which code correctly handles codes 1, 2, and any other code as "Unknown"?
hard📝 Application Q8 of 15
Kotlin - Control Flow as Expressions
You want to assign a descriptive string to a variable based on an integer code using when as an expression. Which code correctly handles codes 1, 2, and any other code as "Unknown"?
val desc = when {
code == 1 -> "Start"
code == 2 -> "Stop"
else -> "Unknown"
} correctly uses when without argument and conditions with arrows, including else branch.
Step 2: Identify errors in other options
val desc = when code {
1 -> "Start"
2 -> "Stop"
else -> "Unknown"
}: missing parentheses around the argument (when code { ... }); val desc = when {
code == 1 -> "Start"
code == 2 -> "Stop"
else "Unknown"
}: missing arrow in the else branch (else "Unknown"); val desc = when (code) {
1: "Start"
2: "Stop"
else: "Unknown"
}: uses colons instead of arrows (->).
Final Answer:
val desc = when {
code == 1 -> "Start"
code == 2 -> "Stop"
else -> "Unknown"
} -> Option A
Quick Check:
when with conditions needs arrows and else branch [OK]
Quick Trick:Use arrows and else branch for all when expressions [OK]
Common Mistakes:
MISTAKES
Missing arrow in else branch
Using colons instead of arrows
Omitting else branch
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