You could pre-program your pattern, which imho is elegant and transparent and easily adaptable to more complex situations. 

@pat = ( 0, 1, 1, 0 );
$i = 0;
@result = grep { $pat[ $i++ % 4 ] } 0..12;

[download]

I guess you could also replace "4" with "@pat" to make it even more general.

In reply to Re: Grep Pattern by hdb
in thread Grep Pattern by GotToBTru

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