http://www.perlmonks.org?node_id=412418


in reply to Object inheritance and AUTOLOAD

You would have been better just avoiding AUTOLOAD and generating your functions at compiletime. Not only will this mean you don't have to write a custom ->can, it means that when someone else is debugging this that they won't be confused by functions that only exist after they have been called, that code analysis tools ( all kinds of things in B:: and Devel:: ) are going to work instead of having to just punt, etc.

You should only be using AUTOLOAD like this if you have a real and quantifiable benefit. I recall some code of BrowserUK's that would be a great candidate for AUTOLOAD. That situation involved some hundreds of packages where only a small fraction would ever be used at one time. This isn't true for any code I've seen anyone else ever post. In fact, BrowserUK's example was the only time I've seen there being any benefit to using AUTOLOAD.

package Dog; BEGIN { my @attributes = qw/ bone /; for my $attribute ( @attributes ) { no strict 'refs'; *{"get_$attribute"} = sub { ... }; *{"set_$attribute"} = sub { ... }; } }

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Re^2: Object inheritance without AUTOLOAD
by tilly (Archbishop) on Dec 05, 2004 at 07:03 UTC
    I see that you don't read my posts. :-P

    For an idea of what Larry Wall planned on using AUTOLOAD for, see Shell.

    But that said, I agree that AUTOLOAD is a sledgehammer not to be used lightly. However I'd disagree with you on whether you need to use a custom can if you use AUTOLOAD. See Why breaking can() is acceptable for a fuller explanation of my views.

      Oh ok fine. I use Shell myself but rarely if ever think of it. So you got me. There are other uses for AUTOLOAD than I mentioned and the ones you mentioned are actually useful. I was thinking of the common use of AUTOLOAD to delay method generation. Its that practice that I see is completely out of whack and that I'm thinking of when I complain about people who use AUTOLOAD.

      It also occurs to me that using AUTOLOAD in the way I actually complained about exerts addition runtime penalties that would not normally exist - the entire method cache is invalided whenever the newly generated function is assigned into place.