[erlang-questions] Is this code tail recursive?

Max Lapshin <>
Fri Sep 17 06:24:11 CEST 2010


On Fri, Sep 17, 2010 at 8:14 AM, Ryan Zezeski <> wrote:
> Max, as a newb to Erlang, are you saying that without the module
> qualification and if you imported a function f/0 from another module it
> would instead call that?  Actually, I just went ahead and tried that and the
> compiler gave me an error.  So I ask, what are you referring to?
> -Ryan
>

As for me, I was very inattentive reading erlang tutorial and it was a
surprise for me, when following code didn't upgraded after code
upgrade:

f() ->
  io:format("Hi~n"),
  timer:sleep(500),
  f().


It is very important to use explicit module specification:

f() ->
  io:format("Hi~n"),
  timer:sleep(500),
  ?MODULE:f().

?MODULE is a compile time constant, referring to current module and
this form of call will change code on runtime module update.


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