error using List.filter OCaml -


hy, i'm trying create histogram keep getting error.

histogram example: input :[2;1;2;3;2;1;2;2;5] output :[(2,5);(1,2);(3,1);(5,1)]

my code:

 let rec count ls = match ls   |[]              -> 0   |x::xs  when x=a -> 1 + count xs   |_::xs           -> count xs let rec histo l = match l |[] -> [] |x :: xs ->  [(x, count x l)] @ list.filter(fun x -> xs != x)histo xs;;

error: function has type ('a -> bool) -> 'a list -> 'a list applied many arguments; maybe forgot `;'.

you @ end ;) hints :

  • take care of parenthesis (some missing in code).
  • your filter not correct : (fun (t,_) -> not (t = x)) because histo returns list of tuple.

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