Re: Using Scalar::Util

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At 9:48 AM -0400 6/23/04, Drew Taylor wrote:
>While attending YAPC::NA last week, a talk brought the Scalar::Util 
>module to my attention. Specifically, the blessed() function. This 
>is a neat way to tell if a particular scalar is a blessed object.
>
>How does this relate to Class::DBI? There are LOTS of checks in 
>method calls to make sure it is called either as an instance or 
>class method. They all use something like
>
>sub foo {
>   my $self = shift;
>   # only called as instance method
>   return unless ref $self;
>}
>
>I propose that C::DBI should use blessed() instead since it's a 
>better check. If Tony agrees, I'd be willing to submit a patch. The 
>relevant docs are below. The changes should be pretty easy to make.

In what way is it a "better" check? What case are you worried about 
ref() getting wrong?

The code is trying to make sure you call MyPackage->foo() or 
$my_obj->foo() appropriately, when both of those are reasonable 
things to try.

It seems to me that the only way to call foo() with a reference as 
the first argument that is not an instance of an appropriate class is 
to explicitly do something like MyPackage::foo($randomref), which 
seems to me to be deliberately shooting yourself in the foot, rather 
than something that might accidentally happen.

Am I just missing something?


        -- 
        Aneel Nazareth -- http://eye-of-newt.com/nazareth --