Once you have the string, you can always use eval to turn it into code: 
my $sub = eval "sub { $buildString }";
my @sorted = sort $sub @unsorted;

[download]

Be very careful, though; don't let the user run arbitrary code. Also note that debugging such code is hard.

لսႽ† ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ

In reply to Re: Dynamic sort criteria for an Array in Perl by choroba
in thread Dynamic sort criteria for an Array in Perl by ftonjes

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