A solution could be to take advantage of the possibility to feed sort a reference to a sorting subroutine. That way you could check if the first element is a number (for example with $array[0] =~ /^\d+$/) and select the right subroutine:

my @array = (12,23,34,56,876,324,13) ;
# Use the array below to test for alphas
#my @array = qw(mamma ninnonnina domani festa din don dan) ;

my $sortsub ;
my $sortnum = sub { $a <=> $b } ;
my $sortalpha =  sub { $a cmp $b } ;

$sortsub = $array[0] =~ /^\d+$/ ? $sortnum : $sortalpha ;

my @sorted = sort $sortsub @array ;

print map "$_\n",@sorted ;
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Note however that this approach is far from optimal in this case. In fact when the array contains alphas you replace the fast native sorting with a slower $sortalpha. This approach is better suited for selecting a sort sub in more complicated sorting.

Ciao!
--bronto

# Another Perl edition of a song:
# The End, by The Beatles
END {
  $you->take($love) eq $you->made($love) ;
}