Hi Andy,

I got a question concerning dereferencing hashes and use strict;.
I have a reference to a hash, derived from a reference to a nested hash:

my $hashref = $nested->{"key_to_hash"};

When I dereference that $hashref via

line 35:   my %realhash = %{$hashref};

and when I "use strict" I get the following message:

Can't use an undefined value as a HASH reference at
      /home/user/programming/perl/perlscript.pl line 35 (#1)
    (F) A value used as either a hard reference or a symbolic referenc
+e must
    be a defined value.  This helps to delurk some insidious errors.

[download]

Line 35 is the line where I dereference from $hashref.
When I don't use strict everything works fine...I got no idea what means "defined value" here. All my refs and vars are defined, or am I wrong?

Have a nice day and thanks for the tips yesterday!
Micha

In reply to Re: dereferencing syntax Re: Getting keys/values from a referenced hash by professa
in thread Getting keys/values from a referenced hash by professa

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