Hash of Hashes or Array of Hashes? Or Hash of Arrays which is what your syntax suggests?

Lets say it is an array of hashes:

my @new;
foreach $fn (@old) {
  $new[$fn->{FirstNum}]= $fn;
  delete $fn->{FirstNum}; 
}

[download]

If it is a hash of hashes:

my %new;
foreach $fn (keys %old) {
  $new{$fn->{FirstNum}}= $fn;
  delete $fn->{FirstNum}; 
}

[download]

UPDATE: As an afterthought: Use Data::Dumper. It will show you the right syntax you should have used in your question. And also it will tell you which of the wildly different answers posted in this thread does what you need, if you use it to print the data structure before and after.

In reply to Re: Modifying order of a hash by jethro
in thread Modifying order of a hash by monaghan

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