anchor.diff:                 | None -> raise (new ArgumentException())
       func args
   
  +//Evaluates raw atom, like symbol or number
   let eval_atom (context:Context) atom =
       match atom with
       | Atom (Symbol name) -> 
  
positive.code:             raise (new ArgumentException())
      | _ -> atom //should not be matched, anyway
  
  let eval_defun (gctx:Context) eval fname llist body =
      let arity = List.length llist
      let args = List.map (function |Atom v -> v| _ -> Symbol "nil") llist
  
negative.code: 
  Runtime.load context
  
  //Applies a function to parameters in given context
  let apply (context:Context) (fname_sexp:SExp) (args:SExp) =
      let fname = match fname_sexp with
                  | Atom (Symbol name) -> Symbol name
  