Hi Folks,

I just ran into a problem that I haven't been able to figure out or find an answer to in the Data::Dumper documentation. I hope a Perl Genius can give me a hand :-).

For quite a long time, for a number of different clients, I've been using Data::Dumper to store different types of hashes of hashes to files. They usually have 3 or 4 levels to them.

They syntax that I've always used to print the hash of hashes to a file (successfully until now) is:

use Data::Dumper;
... open file
print FILE Data::Dumper->Dump([\%hash], [*hash]);
... close file


(where 'hash' is the hash name)

It has always worked flawlessly until yesterday.

With this particular script, running on a Linux system with Perl 6.0, the output replaced the usual hash name header, e.g:

%main::email_addresses = (

... with

$VAR1 = {

It also replaced the closing ); with a };

(That is, replacing the () parens with {} curly brackets and replacing the %hash syntax with $VAR1.

Thus, of course, when I tried to read the hash from the file, it didn't exist as a hash.

My kludgy work around was to replace the $VAR1 and other incorrect elements in the file with the right ones.

I noted in the Data::Dumper documentation the line that stated:

"Any references that are the same as one of those passed in will be named $VARn...".

However, in this case the name of the hash is being replaced. Yet, the hash name is not being duplicated anywhere.

This behavior has never happened to me, and I'm completely puzzled.

I also tried to use the statement:

$Data::Dumper::Sortkeys = 1;

in order to force the keys to sort, but when I did so, the hash was completely wiped out.

Does anyone have any thoughts?

Thank you!

Peter Brown

In reply to Problems with Data::Dumper by peterbrown

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