[erlang-questions] Re: try catch scope

[Wes James]

Mangus,

Thanks! This is much better!

has_query(A) ->
	try
		yaws_api:parse_query(A) /= []
	catch
		_:_ -> false
	end.

-wes

On Wed, Jun 30, 2010 at 5:53 AM, Magnus Henoch
<magnus@REDACTED> wrote:
> Wes James <comptekki@REDACTED> writes:
>
>> has_query(A) ->
>>               case length(yaws_api:parse_query(A)) of
>>                       0  -> false;
>>                       _ -> true
>>               end.
>
> A separate note about the code: you should avoid "case length(Foo)" when
> possible, since length/1 needs to traverse the entire list.  Just
> comparing the result to the empty list is probably faster:
>
> case yaws_api:parse_query(A) of
>    [] -> false;
>    _ -> true
> end.
>
> And this can be simplified further:
>
> yaws_api:parse_query(A) /= [].
>
> (There is a difference between my two examples and yours: your code will
> crash with badarg if the result is not a proper list, while mine will
> just return false.)
>
> --
> Magnus Henoch, magnus@REDACTED
> Erlang Solutions
> http://www.erlang-solutions.com/
>
> ________________________________________________________________
> erlang-questions (at) erlang.org mailing list.
> See http://www.erlang.org/faq.html
> To unsubscribe; mailto:erlang-questions-unsubscribe@REDACTED
>
>