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Re: reduce metaoperator on an empty list

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From:
Luke Palmer
Date:
June 1, 2005 06:30
Subject:
Re: reduce metaoperator on an empty list
Message ID:
7ca3f01605060106304d5c29c4@mail.gmail.com
On 6/1/05, Michele Dondi <blazar@pcteor1.mi.infn.it> wrote:
> On Wed, 1 Jun 2005, Luke Palmer wrote:
> 
> >    $ordered = [<] @array;
> >
> > If @array is empty, is $ordered supposed to be true or false?   It
> > certainly shouldn't be anything but those two, because < is a boolean
> > operator.
> 
> I read that (mathematically) as "for all i, for all j such that j-i=1,
> a_i<a_j", which is certainly satisfied by an empty list.

Yep, it sure is.  Now tell Perl to read it that way for any operator.

Luke
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