Actually, I think maybe you're being too nice to your users. :) If they're using the procedural interface, they can access the object via $CGI::Q like so: 
use CGI qw(:standard);

$foo->list_params($CGI::Q);

[download]

Since the procedural interface uses $CGI::Q behind the scenes, there's no need to do the symbol table piggery-jokery you've got. :)

As princepawn was wondering, it's best to check with the isa() method. For any object $foo, you can check to see if it inherits from or is a certain class by saying $foo->isa('CGI'). It is indeed possible that the user could pass a CGI::Fast object, which is a valid CGI object but will fail ref $cgi eq 'CGI'.

So, my rewrite would be: 

package Foo;
use strict;
use Data::Dumper;

sub list_params {
  my ( $self, cgi ) = @_;
  my %formdata;

  defined($cgi) && ref($cgi) && $cgi->isa('CGI')
    or return 0;

  foreach my $key ( $cgi->param ) {
      $formdata{ $key } = _format_vals( [ $cgi->param( $key ) ] );
  }
      
  Dumper( \%formdata );
}

[download]
Note: Code untested.

stephen

In reply to Re: Typeglobs and Symbol tables by stephen
in thread Typeglobs and Symbol tables by Ovid

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