Nested when
structures are difficult to understand because you can easily confuse the cases of an inner when
as belonging
to an outer statement. Therefore nested when
statements should be avoided.
Specifically, you should structure your code to avoid the need for nested when
statements, but if you cannot, then consider moving the
inner when
to another function.
Noncompliant code example
fun foo(n: Int, m: Int) {
when (n) {
0 ->
when (m) { // Noncompliant; nested when
// ...
}
1 -> print("1")
else -> print("2")
}
}
Compliant solution
fun foo(n: Int, m: Int) {
when (n) {
0 -> bar(m)
1 -> print("1")
else -> print("2")
}
}
fun bar(m: Int){
when(m) {
// ...
}
}