150: Learning Kotlin - Returns, Jumps & Labels

Shownotes

• Kotlin Returns and Jumps Documentation

Code data class Customer(val isPlatinum: Boolean) fun main() { val customer = Customer(false) println("Number of points customer has: ${calculatePoints(customer)}") // Break out of the loop once we're over 25 for (i in 1..100) { if (i > 25) { break } else { println(i) } } // Skip all even numbers for (i in 1..100) { if (i % 2 == 0) { continue } else { println(i) } } // Break out of the outer loop (which breaks out of the inner too) using a label donn@ for (i in 1..100) { for (j in 100..200) { if (j > 150) break@donn // This will break out of the inner loop and outer loop else println("i: $i, j: $j") } } // Continue processing the next outer loop value when a condition is met. donn@ for (i in 1..100) { for (j in 100..200) { if (j > 150) continue@donn // This will break out of the inner loop and outer loop else println("i: $i, j: $j") } } // returns with label example1() example2() println("I'm done processing!") } fun calculatePoints(customer: Customer): Int { if (customer.isPlatinum) { return 100000 } else { return 10 } } fun example1() { listOf(1, 2, 3, 4, 5, 6, 7, 8, 9).forEach { if (it > 7) { return } else { println(it) } } println("This wont print :( because return exited the bar() function") } fun example2() { listOf(1, 2, 3, 4, 5, 6, 7, 8, 9).forEach bin@ { if (it > 7) { return@bin } else { println(it) } } println("This will print! :) return exited the forEach!") } Sponsors 🙏

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