How to get element from an erlang list?

Question

I have a list List = [ins_appServer_APP02@mdiaz,ins_appServer_APP04@mdiaz].

and I have an atom that comes as a parameter: AppServerAtom = ins_appServerAPP02@mdiaz

I need help to search in List the element that match with AppServerAtom

It is possible to do this with Erlang?

Possible duplicate of [How to Search for an item in a List in Erlang?](http://stackoverflow.com/questions/673219/how-to-search-for-an-item-in-a-list-in-erlang) — P_A, May 04 '16 at 16:37
Shouldn't it be `AppServerAtom = ins_appServer_APP02@mdiaz` ? — Greg, May 04 '16 at 17:01
A. Sarid : I need to get the element that match with AppServerAtom — md-86, May 04 '16 at 17:54

score 3 · Answer 1 · answered May 04 '16 at 17:18

Use lists:member/2:

List = ['ins_appServer_APP02@mdiaz', 'ins_appServer_APP04@mdiaz'],
case lists:member('ins_appServer_APP02@mdiaz', List) of
  true -> do_something_when_true();
  false -> do_something_when_false()
end.

See http://erldocs.com/current/stdlib/lists.html?i=0&search=lists:mem#member/2 in the Erlang function reference.

score 0 · Answer 2 · answered May 05 '16 at 07:54

0

If you want get the matched element, you can use lists:filter

lists:filter(fun(X) -> X == AppServerAtom end, List).

If you just want check the element is in the List, you can use lists:member

answered May 05 '16 at 07:54

BlackMamba

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How to get element from an erlang list?

2 Answers2