let get_value_of_var (name : string) (var : string) : string =
if(is_a_var var || (name="x" && is_an_aggregation var))
then(
let var_aux = get_name_of_var var in
let hv = Hashtbl.find_all var_value (name,var_aux) in
if(hv=[]) then ("dummy"^var_aux)
else (car hv)
)
else var