Can messages be sent to processes interactively?

[Claes Wikstrom]

> 
> I've been doing a lot of sequential programming in Erlang, but have just
> started getting into concurrency.  It seems very obvious and
> straightforward.
> 
> I wrote a quickie test process so I can start it up and send messages to
> it interactively, just so I know that all is well:
> 
> -module(sample).
> -export([start/0]).
> 
> start() -> spawn(sample, server, []).
> 
> server() ->
>    receive
>       stop -> ok;
>       Msg  ->
>          io:fwrite("message received: ~w\n", [Msg]),
>          server(N)
>   end.
> 


And yet another little error, there is no function
called sample:server/0 nor sample:server/1 *exported*
from the module.

It might seem pretty idiotic that any function that is spawned
need to be exported but that is the way it is.

(applies to apply/3 too !!!)

So, change 

> -export([start/0]).

to

-export([start/0, server/0]).

Personally I like the

-compile(export_all)

switch while I'm developing, this way I need not bother
about that at that stage.


Cheers

/klacke

PS. There's  a bit of one of my favourite topics in here -- namely
software archeology. Why is it like this. The obvious thing would
be to spawn a fun instead of a tripple M:F/A

start() -> 
	spawn(fun() -> server() end).

????