Right - the second time you try that sort, $a and $b are undef each time the block is evaluated. Furthermore, it appears that sort-within-sort only breaks if the inner sort is in a different package than the outer sort, as you'll notice that when I do the sort myself (inside main) there's no problem.

Also, see my other reply that exhibits this phenomenon without using AI::Genetic. 

--
@/=map{[/./g]}qw/.h_nJ Xapou cets krht ele_ r_ra/;
map{y/X_/\n /;print}map{pop@$_}@/for@/

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In reply to Re^2: AI::Genetic gives me strange warnings by fizbin
in thread AI::Genetic gives me strange warnings by fizbin

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