Constant lists

Klacke <>
Mon Jun 26 09:52:19 CEST 2000


On Mon, Jun 26, 2000 at 07:57:59AM +0200, Torbjorn Tornkvist wrote:
> 
> > In Erlang, you could do this:
> > 
> > constant_list() -> [item1, item2, item3, item4, ...].
> 
> Or this:
> 
>  -define(CONSTANT_LIST, [item1, item2, item3, item4, ...] ).
> 
>  ...
>  X = ?CONSTANT_LIST,
>  ...


Which ain't that good either since it will also recreate
the list every time the macro is used.
No I suggest using the dictionary,

new_const_list() -> [1,2,3,4,5,6,7].

const_list() ->
	case get(const_list) of
		undefined ->
			N = new_const_list(),
			put(const_list, N),
			N;
		List ->
			List
	end.


/klacke


-- 
Claes Wikstrom                          <>
Bluetail AB                             http://www.bluetail.com





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