let path = {|/bin:/usr/bin:/home/user/horrible\:path|}

let should_escape char_stack c =
    not (Stack.is_empty char_stack)
    && Stack.top char_stack = "\\"

let a char_stack c =
    Stack.push (
        (
            if (should_escape char_stack c)
            then (Stack.pop char_stack)
            else ""
        ) ^ (String.make 1 c)
    )  char_stack ;
    char_stack


let proto_paths = String.fold_left a (Stack.create()) path

let b string_stack c =
    Stack.push (
       if c = ":"
       then ""
       else (Stack.pop string_stack) ^ c
    ) string_stack ;
    string_stack

let paths = Stack.fold b  (Stack.create()) proto_paths

let () = Stack.iter print_endline paths