To add to this, at some point the community, even Elixir codebase, settled on do_send_message as a convention but today we see it as a bad practice. We are trying our best to not use do_ prefixes in Elixir and use proper function names for them, even if it ends up being the original name with extra information, for example, check_shortname_and_send_message.

You can pattern match the handle_command function to drop the first if

defp handle_command({"msg", "remove-trigger", cmd}, {%{data: %{"author" => %{"id" => 1234}}}, state}) do
   # handle author 1234  
end
defp handle_command({"msg", "remove-trigger", cmd}, {payload, state}) do
  # No-op because you have no else
end

For the second if I would drop the call to Message.has/1 (assuming Message.get/1 returns nil for no message)

shortname = String.split(cmd, " ") |> List.first
do_send_message(Messages.get(shortname))

Then have a function deal with the presence or lack of message

defp do_send_message(nil) do
  send_message "unknown Message", {payload, state}
end
defp do_send_message(info) do
  trigger = …
end

Keep going by creating functions that handle each situation and try to come up with names that reveal the intent of each step (do_send_message is a terrible function name but because naming is hard, you get to solve that )

Thanks a lot guys, this really helped me. It’s really easy for me to forget how powerful the pattern matching just is. I know Rust’s pattern matching which is pretty cool already, but this is way more powerful.

I’m new to elixir as well and still figuring this out. But one thing you can do is break this up into more functions and take advantage of pattern matching.

For instance you can get rid of the first if statement by pattern matching the handle_command function:

defp handle_command({ "msg", "remove-trigger", cmd }, { %{data: %{"author" => %{"id" => 1234}}}, state }) do