Passing an object to a module

[gmills]

Hello -

I am creating a module that does some work for various CGI in my
system. I would like to pass the CGI object to subroutines in my
module, but I can't figure out how to do it. Right now, I'm taking a
reference to the variable that holds the object in my CGI, like this:

use CGI;
use MYMODULE;

$q = new CGI;

MYMODULE::subroutine(\$q);

But if, for example, in MYMODULE, I do this:

use CGI;

sub subroutine {

$qref = shift;
$q = $$qref;

foreach $name ($q->params) {


I get the message that CGI:arams is an undefined subroutine, when it
should be the names of the parameters passed to the CGI script.

Can anyone tell me what I am doing wrong?

Thanks;

Garey Mills

 

[Scott Bryce]

Hello -

I am creating a module that does some work for various CGI in my
system. I would like to pass the CGI object to subroutines in my
module, but I can't figure out how to do it. Right now, I'm taking a
reference to the variable that holds the object in my CGI, like this:

<code snipped>

That variable is a reference to a hash.

use strict;
use warnings;
use CGI;

my $query = new CGI;

my $string = somesubroutine($query);

print "Content-type: text/plain\n\n";
print $string;

sub somesubroutine
{
my $cgi = shift;

return $cgi->param('abc')
}

 

[Gunnar Hjalmarsson]

foreach $name ($q->params) {

-------------------------------^

http://perldoc.perl.org/CGI.html#FETCHING-THE-NAMES-OF-ALL-THE-PARAMETERS-PASSED-TO-YOUR-SCRIPT:

 

[Brian McCauley]

That variable is a reference to a hash.

"That" is unclear.

By which I mean that is unclear to what you are referring by the
pronown "that".

The "variable that holds the [CGI] object" that the OP refers to is a
variable that holds a reference to a thingy (that happens to be a hash)
that's been blessed into the class 'CGI'.

I think the point you are trying to make is that objects in Perl are
always handled via references so an extra level of indirection is
unecessary.

 

[Jim Gibson]

Hello -

I am creating a module that does some work for various CGI in my
system. I would like to pass the CGI object to subroutines in my
module, but I can't figure out how to do it. Right now, I'm taking a
reference to the variable that holds the object in my CGI, like this:

use CGI;
use MYMODULE;

$q = new CGI;

MYMODULE::subroutine(\$q);

But if, for example, in MYMODULE, I do this:

use CGI;

sub subroutine {

$qref = shift;
$q = $$qref;

foreach $name ($q->params) {


I get the message that CGI:arams is an undefined subroutine, when it
should be the names of the parameters passed to the CGI script.

There is no params() method. Call param() in list context without
arguments to get the names of the parameters passed to the CGI script.

See 'perldoc CGI' for available methods and how to use them.

 

[Scott Bryce]

I think the point you are trying to make is that objects in Perl are
always handled via references so an extra level of indirection is
unecessary.

Yes. That is the point I was trying to make. Thank you for clarifying.