It doesn't work because your loop walks down a chain of hash references, but you don't retain the first reference in the chain anywhere, and at the end of the loop, you clobber the reference you have ($h) with some (presumably plain) scalar value ($val).

I made some changes. 

use Data::Dumper;

my $list = [ "k0", "k1", "k2", ];
my ($h,$t);
$t = $h = {};
foreach my $k ( @{$list}[ 0 .. $#{$list}-1 ] ) {
    $t->{$k} = {};
    $t = $t->{$k};
}
$t->{$list->[-1]} = 'val';

print Dumper $h;
__END__
$VAR1 = { 
          'k0' => { 
                    'k1' => { 
                              'k2' => 'val'
                            }
                  }
        };

[download]

Having gone through all that, however, you might want to look into Data::Diver for this kind of thing.

In reply to Re: adding keys to a hash by kyle
in thread adding keys to a hash by Anonymous Monk

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