Hello, I have a question regarding the use of hashes. I'm reading some tutorials a the moment and it uses the following as an example of a hash table variable:

my $address = {
                  Name    =>  'Bernd Dulfer',
                  Str     =>  'Kapellenstr. 1',
                  EMail   =>  'bdulfer@sybase.com',
                  Books   =>  [
                               'Lord of the Rings',
                               'Hitchhikers Guide to the Galaxy',
                               'The Color of Magic'
                              ]
              };
print 'Other name: ', $address->{Name}, "\n";

[download]

Is $address just being used as a reference in this context? What's the difference if I do the following:

my %address = (
                  Name    =>  'Bernd Dulfer',
                  Str     =>  'Kapellenstr. 1',
                  EMail   =>  'bdulfer@sybase.com',
                  Books   =>  [
                               'Lord of the Rings',
                               'Hitchhikers Guide to the Galaxy',
                               'The Color of Magic'
                              ]
              );
print 'Other name: ', %address->{Name}, "\n";

[download]

I noticed that the compiler noted that accessing a hash like that is deprecated. The former is a reference, and the following is directly accessing the variable, no? If the latter is deprecated, should I use the former method to always refer to a hash table? Thank you!

Edit: Also, why would adding a key to the hash cause a compilation error? E.g.

my $address{Bernd} = {

causes

syntax error at ./sixth.pl line 14, near "$address{Bernd"
Execution of ./sixth.pl aborted due to compilation errors.

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What causes that?

In reply to Regarding Initialization and Use of Hashes by Zaemz

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