I know this function already exists, but here is my idea of implementation.

tuple_to_list.erl

% Converts a tuple to a list.
% {a, b, c, d} -> [a, b, c, d]
tuple_to_list(T) ->
	tuple_to_list(T, 0).

tuple_to_list(_T, -1) ->
	[];

tuple_to_list(T, Id) ->
	Max = tuple_size(T) - 1,
	E = if
		Id > Max ->
			Nid = -1,
			[];

		true ->
			Nid = Id +1,
			[element(T, Id)]
	end,
	lists:append(E, tuple_to_list(T, Nid)).