Variable
As variable assignment:
var checker: str = if (variable){ 
    in {..10} -> "in range of 1-10"; 
    in {11..20} -> "in range of 11-20";
    * -> "out of range";
}
var is_it: int = if (variable){ 
    is "one" -> 1; 
    is "two" -> 2; 
    * -> 0;
}
var has_it: bol = if (variable){ 
    has "o", "k" -> true; 
    * -> false;
}
Function
As function return:
fun someValue(variable: int): str = if (variable){ 
    in {..10} -> "1-10"; 
    in {11..20} -> "11-20"; 
    * -> "0";
}