Can't use an undefined value as a HASH reference

You're trying to reach a variable via a type glob in the symbol table, yet the variable in question isn't in the symbol table. It's a lexical (my) variable.

How can I use a type glob to get at the hash's values?

Implicitly, if the glob is in the symbol table: 

my %h1 = qw{a 1 b 2};
*h2 = \%h1;             # Create and initialise glob
print %h2, "\n";        # Access hash referenced by glob

[download]

Explicitly, if the glob is in the symbol table: 

my %h1 = qw{a 1 b 2};
*h2 = \%h1;             # Create and initialise glob
print %{*h2}, "\n";     # Access hash referenced by glob

[download]

Indirectly, if the glob is in the symbol table: 

my %h1 = qw{a 1 b 2};
my $glob = *h2;         # Create glob
*$glob = \%h1;          # Initialise glob
print %$glob, "\n";     # Access hash referenced by glob

[download]

Indirectly, if the glob is outside the symbol table: 

sub new_glob { return local *X }

my %h = qw{a 1 b 2};
my $glob = new_glob();  # Create glob
*$glob = \%h;           # Initialise glob
print %$glob, "\n";     # Access hash referenced by glob

[download]

I am trying to use a type glob to access values in a hash.

Why?

In reply to Re: type glob by ikegami
in thread type glob by 7stud

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