Returns this value decremented by one.
Since Kotlin
1.5Samples
fun main() {
//sampleStart
val a = 3
val b = a.dec()
println(a) // 3
println(b) // 2
var x = 3
val y = x--
println(x) // 2
println(y) // 3
val z = --x
println(x) // 1
println(z) // 1
//sampleEnd
}