Kotlin continuing to else clause after return

I am trying to figure out how returns work in Kotlin. Right now I have a function that with two nested for loops.

All returns should return for the parent function getValue(), one seems to work as expected, the other one does does not.

val myArray = arrayOf(
MyObj("String 1", mapOf(Pair(MyEnum.apple, "String 2"))),
MyObj("String 2", mapOf(Pair(MyEnum.orange, "String 1"),
Pair(MyEnum.apple, "String 3"))),
MyObj("String 3", mapOf(Pair(MyEnum.orange, "String 2")))
)

val myObj = myArray[1]

fun main(args: Array<String>) {
getValue(MyEnum.apple)
}

fun getValue(myEnum: MyEnum) {
myObj.myMap.forEach { (enum, str) ->
if (enum == myEnum) {
myArray.forEach {obj ->
if (obj.name == str) {
if (checkStuff(obj)) {
println("checkStuff returned true")
return // this continues to printLn
}
println("returned false")
return // This appears to return as expected
}
}
} else {
println("Should not be hit")
}
}
}

fun checkStuff(obj: MyObj): Boolean {
return obj.name == "String 1"
}

data class MyObj (val name: String, val myMap: Map<MyEnum, String>)

enum class MyEnum {
apple, orange, pear
}


The return inside the checkStuff if always continues onto the printLn.

From reading through documentation, I thought that adding return@getValue would return for the top level function and exit out of that function.

I seem to be missing something. How would I make the first return not continue on to the else clause with the printLn?

return

getValue

checkStuff

false

if

2 Answers
2

You need to fix your if-statements logic,
at current state checkStuff can't return true

checkStuff

true

fun getValue(myEnum: MyEnum) {
myObj.myMap.forEach { (enum, str) ->
if (enum == myEnum) { // Pair(MyEnum.APPLE, "String 3")
myArray.forEach { obj -> // str = "String 3"
if (obj.name == str) { // obj.name = "String 3"
if (checkStuff(obj)) { // "String 3" == "String 1"
// checkStuff: obj.name == "String 1"
...
}
...


The return statements work fine. The problem with your code is that the only time checkStuff(obj) gets called it returns false, therefore the following is never called:

checkStuff(obj)

`println("checkStuff returned true")
return // this continues to printLn`


If you make the appropriate changes to fun checkStuff(..) {...} you will find that the code works just like you expected.

fun checkStuff(..) {...}

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