[erlang-questions] Bound(?) var in anonymous fun
Loïc Hoguin
essen@REDACTED
Tue Dec 18 12:36:25 CET 2012
This one only removes the first element. :)
On 12/18/2012 12:34 PM, Max Bourinov wrote:
> Or even more shooter:
>
> lists:delete(Key, StatusList).
>
>
> On Tue, Dec 18, 2012 at 3:22 PM, Dmitry Klionsky <dm.klionsky@REDACTED
> <mailto:dm.klionsky@REDACTED>> wrote:
>
> On 12/18/2012 02:08 PM, Manuel A. Rubio "Bombadil" wrote:
>
> Hi Pablo,
>
> El 2012-12-18 11:54, Pablo Vieytes escribió:
>
> I guessed Key was bound so I could use for pattern matching.
> It's
> very easy to fix it but I don't know why it doesn't work.
>
>
> This doesn't works well because the params are not inside of
> binding in closures. The params are the interface with the
> outside world and will be confuse know if a param is a binding
> or not. By default Erlang hasn't binding in function params.
>
> Fixed version:
>
> delete_key_from_list(Key, StatusList)->
> lists:foldr(
> fun(K, Acc) when K == Key ->
> Acc;
> (Another, Acc) ->
> [Another|Acc]
> end,
> [],
> StatusList).
>
>
> This code could be writted as:
>
> delete_key_from_list(Key, StatusList)->
> lists:filter(fun(X) -> Key =/= X end, StatusList).
>
> Regards,
> Manuel Rubio.
> _________________________________________________
> erlang-questions mailing list
> erlang-questions@REDACTED <mailto:erlang-questions@REDACTED>
> http://erlang.org/mailman/__listinfo/erlang-questions
> <http://erlang.org/mailman/listinfo/erlang-questions>
>
>
> Or even more readable as:
>
> delete_key_from_list(Key, StatusList)->
> [Status || Status <- StatusList, Status =/= Key].
>
> --
> Best regards,
> Dmitry Klionsky
>
>
> _________________________________________________
> erlang-questions mailing list
> erlang-questions@REDACTED <mailto:erlang-questions@REDACTED>
> http://erlang.org/mailman/__listinfo/erlang-questions
> <http://erlang.org/mailman/listinfo/erlang-questions>
>
>
>
>
> _______________________________________________
> erlang-questions mailing list
> erlang-questions@REDACTED
> http://erlang.org/mailman/listinfo/erlang-questions
>
--
Loïc Hoguin
Erlang Cowboy
Nine Nines
http://ninenines.eu
More information about the erlang-questions
mailing list