Re: dereferencing

On Monday 29 October 2007 15:23, Aaron Priven wrote:
I can do this:

my $hashref = \%hash;

But as near as I can tell, there is no way to do the reverse
operation: making a "my %hash" that is an alias for a hash reference.

Correct. You can alias a package variable but not a lexical variable.


It's possible with a package variable:

#/usr/bin/perl
our %hash;
my $hashref = { a => 5 , b => 8 };
*hash = $hashref;

You are not assigning to %hash you are assigning to the typeglob *hash.
Because $hashref contains a reference to a hash only the *hash{ HASH }
entry in the symbol table is affected.


print $hash{a};

that prints "5". But there's no way to do this with a lexical (my)
variable.

is this right?

Correct. Lexical variables are not part of the symbol table.



John
--
use Perl;
program
fulfillment

.

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