I think that mangling the keys by adding a prefix could quickly get out of hand and become difficult to manage, with strategies required if the number of sections goes over 26 etc. If you have one particular key, as in the OP, that has to come first then sort on whether you have found that key before the lexical sort, like this

#!/usr/local/bin/perl -l
#
use strict;
use warnings;

my %sections = (
   DMA  => q{dma},
   FST  => q{dma/fst},
   MRA  => q{dma/mra},
   BKS  => q{bks},
   MSU  => q{dma/msu},
   FMA  => q{dma/fma},
   FOMC => q{dma/FOMC});

my $thisKeyFirst = q{DMA};

my @sortedKeys =
   map  { $_->[0] }
   sort { $b->[1] <=> $a->[1] || $a->[0] cmp $b->[0] }
   map  { [$_, $_ eq $thisKeyFirst] }
   keys %sections;

print for @sortedKeys;

[download]

which produces

DMA
BKS
FMA
FOMC
FST
MRA
MSU

[download]

It seems to me that it would be easier to manage that way. It you had a few special keys that fell into this category this method would still work but with a hash to hold the order of the specials, highest value first and keys not in specials hash getting zero. Something like (not tested)

my %specials = (
   DMA => 2,
   MSU => 1);

...

   map  { [$_, exists $specials{$_} ? $specials{$_} : 0] }
   keys %sections;

[download]

Cheers,

JohnGG

In reply to Re^2: Turning a hash into a line of links by johngg
in thread Turning a hash into a line of links by OfficeLinebacker

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