Actually, you have more than one problem. The first is not using strict. The second is that you define your hash as a hash reference, but try to use at as a hash. But why are you using index numbers as keys for a hash? Wouldn't an array be better? Yes. An array of hash references as a matter of fact - a list of hashes (LoH): 
use strict;
use Data::Dumper;

my @shape;

for (0..9) {
   unless ($_ % 2) {
      $shape[$_]->{shape} = 'rect'
   }
   else {
      $shape[$_]->{shape} = 'circle'
   }
   $shape[$_]->{coords} = [0,1,2,3,4,5,6,7,8,9];
}

# what does it look like now?
print Dumper \@shape;

# and to get that slice:
for (0..$#shape) {
   print "shape $_ is a ", $shape[$_]->{shape},
      " (", join(',',@{$shape[$_]->{coords}}[0..3]), ")\n";
}

[download]
Hope this helps. Note the use of Data::Dumper - always use it when you are molding your data structures. It is a true life saver. ;)

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

In reply to (jeffa) Re: Correct syntax to access an array slice within a hash within a hash by jeffa
in thread Correct syntax to access an array slice within a hash within a hash by Popcorn Dave

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