I stand by what I said. Even just hardcoding the 4 warranted horror. And you are mistaken about the restrictiveness of my code. 

@a[ grep { $pat[ $_ % @$pat ] } 0..$#a ]

[download]
or 
sub filter_by_pat {
   my $pat = shift;
   return @_[ grep { $pat->[ $_ % @$pat ] } 0..$#_ ];
}

filter_by_pat [0,1,1,0], ...

[download]

In reply to Re^4: Grep Pattern by ikegami
in thread Grep Pattern by GotToBTru

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