[erlang-questions] List comprehension puzzler

Richard A. O'Keefe <>
Thu Sep 22 03:07:41 CEST 2016



On 21/09/16 11:23 PM,  wrote:
> I'd like to point out that it's straightforward to write
> >     ...
>
> It's not much harder to write
>
> length_between([_|Xs], L, U) when L > 0 ->
>     length_between(Xs, L-1, U-1);
> length_between([], L, U) ->
>     L =< 0, 0 =< U;
> length_between(_, _, _) ->
>     false.

The third clause was *meant* to be

   length_between([], L, U)
     when L =< 0, 0 =< U -> true;

Free code.  Worth every mill.
Thanks to Fred Hébert for noticing this.
Too much coffee, too late at night, and too much
frustration with AirPort losing the signal every
few seconds.



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