October 2025
Intermediate to advanced
100 pages
2h 27m
English
Content preview from Kotlin Brain Teasers
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| Puzzle 7 | Anything You Want Me to Be |
| | sealed interface Creature |
| | |
| | object Dragon : Creature |
| | object Unicorn : Creature |
| | object Yeti : Creature |
| | |
| | fun main() { |
| | val mysteryFootprints: Yeti? = null |
| | |
| | when (mysteryFootprints) { |
| | is Dragon? -> println("Looks like the claw-marks of a huge dragon.") |
| | is Unicorn? -> println("I see the hoof-prints of a magical unicorn.") |
| | is Yeti? -> println("These huge footprints prove the yeti is real!") |
| | null -> println("There aren't any footprints.") |
| | } |
| | } |
Guess the Output | |
|---|---|
|
Try to guess the output (or error) ... |
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I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.