So, I’m writing my home project with Elixir, everything’s going fine, decided to plug dialyxir to scan for some potential issues and it gives me this one error:
lib/http_server.ex:60:unmatched_return
The expression produces a value of type:
:ok | pid()
but this value is unmatched.
Code in question:
defp accept_loop(listen_socket, %State{} = state) do
state = %{state | total_calls: state.total_calls + 1}
case :gen_tcp.accept(listen_socket) do # LINE 60, issue is here
{:ok, client_socket} ->
spawn(fn -> serve(client_socket, state) end)
{:error, data} ->
Logger.notice("Error accepting client socket - #{inspect(data)}")
end
accept_loop(listen_socket, state)
end
Error about unmatched value from gen_tcp.accept. Everything’s working fine and according to documentation I’m matching values just fine - Erlang -- gen_tcp :
It’s the case statement itself that returns either pid from first match - spawn is called - or :ok from second match - Logger.notice call - and THAT is unmatched. So, with this insight, this is an easy “”“fix”"", as I don’t give a damn about what case returns.
defp accept_loop(listen_socket, %State{} = state) do
state = %{state | total_calls: state.total_calls + 1}
_ = case :gen_tcp.accept(listen_socket) do
{:ok, client_socket} ->
spawn(fn -> serve(client_socket, state) end)
{:error, data} ->
Logger.notice("Error accepting client socket - #{inspect(data)}")
end
accept_loop(listen_socket, state)
end