I believe @a = sort @a; works in place. O(1N) memory, O(NN log N) time. 

my @keys;
keys(%hash);  # Reset iterator
#while (my $k = each(%hash)) {  # if 0 or '' are possible keys
while (my $k = each(%hash)) {
   push @keys, $k;
}

@keys = sort @keys;
for (0..$#keys) {
   $hash{$keys[$_]} = $_;
}

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In reply to Re: In-place sort with order assignment by ikegami
in thread In-place sort with order assignment by BrowserUk

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