The last item is always an array but I have an arbitrary number of keys

I'm not clear how an item (singular) can be an array, so what follows may not be exactly what you want, but it should give you a basis from which you can work. 

use Data::Diver qw( DiveRef );

my $data;

while (<DATA>) {
   chomp;
   my @keys = split /:/;
   my $val = pop(@keys);
   my $ref = DiveRef( $data, map \$_, @keys );
   push @$ref, $val;
}

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Data::Diver

In reply to Re: HoH..oA data structure by ikegami
in thread HoH..oA data structure by Anonymous Monk

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