I am trying to write a method that can accept as input a CGI.pm like object. Instead of using 'isa' to find out if it is a CGI.pm object, I would like to check if the module provides the methods I am looking for using UNIVERSAL::can. This way other modules like CGI::Simple or Apache::Request can also be used.

What I am wondering is, what is the cleanest way to deal with the fact that CGI.pm autoloads methods on demand, hiding them from UNIVERSAL::can. The only thing I can come up with is actually calling the method in question in an eval {} first and then checking it with UNIVERSAL::can...

use CGI ();
my $q = CGI->new;

print "can cookie: ", UNIVERSAL::can($q, 'cookie') ? 'Yes' : 'No', $/;
eval { $q->cookie };
print "can cookie: ", UNIVERSAL::can($q, 'cookie') ? 'Yes' : 'No', $/;

[download]
can cookie -> No
can cookie -> Yes

But I was hoping there was a cleaner way to do this without actually having to call the method.

CGI::Simple doesn't seem to suffer from this since it uses AutoLoader, which will create stubs for the autoloaded subroutines, but CGI.pm uses it's own method...

In reply to UNIVERSAL::can and autoloaded methods by cees

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