This is my best guess. =)
#!/usr/bin/perl

use strict;
use warnings;
use Data::Dumper;

my @a = qw(1 2 3 4 5 6 7 8 9);

my $h = {}; my $t = $h;
map { ($t = $t->{$_} = ($_ eq $a[-1])? undef : {})  } @a;

print Dumper($h);

[download]

But as always, use at your own risk.

Cheers!
--habit

In reply to Re: Array to nested hash by habit_forming
in thread Array to nested hash by amw1

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