Erlang's Open Telecom Platform (OTP) Framework [video]

lelf wrote: post #3

And if you haven't seen it, here is some classic. “Erlang: the Movie”: — http://www.youtube.com/watch?v=xrIjfIjssLE And sequel “Erlang: the Movie II”: — http://www.youtube.com/watch?v=rRbY3TMUcgQ Don't think wtf. Just watch.

I have a mug etched with a picture from that movie (by way of Learn You Some Erlang For Great Good): https://twitter.com/silentbicycle/status/299278899886579712 :)

Re: Erlang's Open Telecom Platform (OTP) Framework [video]

#5

Post by lpgauth » Mon, May 06, 2013, 1:00 PM UTC

Clause order matters.

--

  -module(ping).
  -export([ping/2]).

  ping(N, Pid) ->
      Pid ! ping,
      receive
          pong ->
              ping(N-1, Pid)
      end;
  ping(0, _Pid) ->
      ok.

  erlc ping.erl
  ping.erl:10: Warning: this clause cannot match because a
  previous clause at line 4 always matches

Re: Erlang's Open Telecom Platform (OTP) Framework [video]

#6

Post by vinoski » Mon, May 06, 2013, 1:42 PM UTC

lpgauth wrote: post #5

Clause order matters. -- -module(ping). -export([ping/2]). ping(N, Pid) -> Pid ! ping, receive pong -> ping(N-1, Pid) end; ping(0, _Pid) -> ok. erlc ping.erl ping.erl:10: Warning: this clause cannot match because a previous clause at line 4 always matches

Correct -- immediately after the video was posted to InfoQ I posted a comment there to clarify and correct that error:

http://www.infoq.com/presentations/Erlang-OTP-Behaviors#anch...