David Christensen writes:
> Hypothetical here:
> If we want to calculate a set of values for a junction which map nicely 
> to a range with a few outliers, would it be possibly to have a 
> qualifier :except which allows us to make exceptions to our given 
> range?  I.e.,
> (Ignore for the moment the inefficiency of the choice of this 
> particular algorithm.)
> my $year = 1900;  # or whatever
> my $leap_year = $year % 400 == any(0..400 :by(4) :except(100,200,300));
> Here except would be a modifier on the range being generated for any(). 
>  I could also see except being used to "strip choices" from junctions:
> my $j = 1|2|3|4;
> my $k=$j :except(2);  # 1|3|4
> Let me know if I'm totally abusing junctions here...

No, you're abusing adverbs.  You can't give an adverb to a variable
(because adverbs don't modify actually nouns :-).  I don't know if we've
destroyed Damian's comparator semantic, but if not, then you can just

    my $k = ($j != 2);

But if that no longer happens, it's best a method on the junction.
Except every time we add a method to junction, we destroy the ability to
automatically thread that method over the junction.  I've proposed
several solutions to this over the years (applying to autodelegating
iterators as well).  I still think it's something that that needs to be


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