examples/higher.spl

   1 map(f, l){
   2         if(isEmpty(l)){
   3                 return [];
   4         } else {
   5                 return f(l.hd) : map(f, l.tl);
   6         }
   7 }
   8
   9 foldr(f, acc, l){
  10         if(isEmpty(l)){
  11                 return acc;
  12         } else {
  13                 return foldr(f, f(acc, l.hd), l.tl);
  14         }
  15 }
  16
  17 filter(f, l){
  18         if(isEmpty(l)){
  19                 return [];
  20         } else {
  21                 if(f(l.hd)){
  22                         return filter(f, l.tl);
  23                 } else {
  24                         return l.hd : filter(f, l.tl);
  25                 }
  26         }
  27 }
  28
  29 intList(x){
  30         [Int] l = [];
  31         Int a = 1;
  32         while(a <= x){
  33                 l = a : l;
  34                 a = a + 1;
  35         }
  36         return l;
  37 }
  38
  39 printIntList(l) :: [Int] -> Void{
  40     print('[');
  41         if(!isEmpty(l)){
  42                 print(l.hd);
  43                 l = l.tl;
  44         }
  45         while(!isEmpty(l)){
  46                 print(", ", l.hd);
  47                 l = l.tl;
  48         }
  49         print("]\n");
  50 }
  51
  52 main(){
  53         print("faculty of 5 is: ", foldr(\x y->x*y, 1, intList(5)));
  54         print("sum of 1..5 is: ", foldr(\x y->x+y, 0, intList(5)));
  55         print("filter evens from 0..12 is: ");
  56         printIntList(filter(\x->x%2 == 0, intList(12)));
  57     printIntList(1:2:3:[]);
  58 }