Hello, I'm trying to implement a fairly involved data structure incorporating a hash of hashes, but I'm running into a LOT of difficulties, and I'm really stuck. I've written a demo program which exhibits the same problems. The following seems to run OK:

    

#!usr/bin/perl -w 
 
use strict; 
 
my @names = ("Tom", "Mary", "Nat", "Luke"); 
 
my %people; 
 
for(my $i=0; $i < @names; $i++) { 
  $people{$names[$i]}={}; 
  $people{$names[$i]}{number}=$i; 
  $people{$names[$i]}{numbx2}=$i*2; 
} 
 
foreach my $key (keys(%people)) {
print "\n".$key."\t".$people{$key}{numbx2}."\t".$people{$key}{number};
}
[download]

But Perl doesn't seem to like this at all:

#!usr/bin/perl -w 
 
use strict; 
 
my @names = ("Tom", "Mary", "Nat", "Luke"); 
 
my %people; 
 
for(my $i=0; $i < @names; $i++) { 
  $people{$names[$i]}={}; 
  $people{$names[$i]}{number}=$i; 
  $people{$names[$i]}{numbx2}=$i*2; 
} 
 
foreach my $key (keys(%people)) { 
  foreach my $pkey (keys($people{$key})) { 
    print "\n".$key."\t".$people{$key}{$pkey}; 
  } 
}
[download]

Also if I change the innermost foreach line to read

foreach my $pkey (keys(%people{$key})) {

(note the change from $ to %) -- which intuitively I would have thought was correct -- I also can't get the program to run.

I have read through the Perl documentation on a hash of hashes, but it's not terribly enlightening. After several infuriating hours I'm well and truly stuck -- any help is greatly appreciated.

Thanks very much.

Luke

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