In Kotlin, functions can be passed as arguments to other functions, returned from functions, stored in variables.
In the code below a function add is declared as a lambda and passed as argument to the function calc:
val add ={a: Int, b: Int ->a+ b}
fun calc(i1:Int, i2: Int, action : (p1: Int, p2: Int) -> Int) {
var result = action (i1, i2)
}
//usage
calc(add)
In the code below a function add is declared as an anonymous function and passed as argument to the function calc:
val add =fun(a: Int, b: Int) =a+ b
fun calc(i1:Int, i2: Int, action : (p1: Int, p2: Int) -> Int) {
var result = action (i1, i2)
}
//usage
calc(add)
Returning a function that accepts a string and returns nothing:
fun displaMsg(msg : String) : (String) -> Unit {
return { s -> println ("$msg is $s" ) }
}
val d = displayMsg("error")
d("401")
//output is "error is 401"
miniguide 