October 2025
Intermediate to advanced
100 pages
2h 27m
English
Content preview from Kotlin Brain Teasers
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.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.
| Puzzle 23 | Bringing Up the Rear |
| | fun downloadFile( |
| | onError: (String) -> Unit = { error("Missing failure callback") }, |
| | onSuccess: (String) -> Unit = { error("Missing success callback") } |
| | ) { |
| | try { |
| | onSuccess("Download successful!") |
| | } catch (error: Throwable) { |
| | onError("Something went wrong: " + error.message) |
| | } |
| | } |
| | |
| | fun main() { |
| | downloadFile { result -> println("1. $result") } |
| | downloadFile({ result -> println("2. $result") }) |
| | } |
Guess the Output | |
|---|---|
|
Try to guess the output (or error) before moving to the next page. |
The program displays ...
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
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.