Beefy Boxes and Bandwidth Generously Provided by pair Networks
Just another Perl shrine
 
PerlMonks  

Re: Re: Re: Re: Often Overlooked OO Programming Guidelines

by Ovid (Cardinal)
on Dec 30, 2003 at 07:06 UTC ( #317637=note: print w/ replies, xml ) Need Help??


in reply to Re: Re: Re: Often Overlooked OO Programming Guidelines
in thread Often Overlooked OO Programming Guidelines

I'd prefer to write that $self->Foo::_fiddle, even though it would be slower.

And that now means you're hardcoding the package name into the method call. Still, since you're staying within the package, this might not be a Bad Thing. I'll have to think about that.

Don't understand what problem/assumptions [with a private method reaching into the object which ]you see as problematic here. Can you elaborate?

This can be a problem if you're subclassing. Let's say that a Tiger is a subclass of Animal and the creator of package Tiger; decides that a blessed array reference is the way to go. With proper encapsulation, this should be irrelevant. However, when you find out that package Animal; is a blessed hashref, that's probably how you will have to implement Tiger. Once you pick how to represent a particular class, you're likely stuck with it once you subclass.

Meanwhile, your tiger object must be uniquely identified, so you decide to create an MD5 digest for it:

sub id { $self->{_digest} ||= $self->_create_new_digest; }

Meanwhile, you've failed to realize that the Animal class has a private "_digest" key in the hashref to let it know if it's busy digesting food. That could be a real pain to debug, but you have to know your superclass's internals to avoid problems like this.

Cheers,
Ovid

New address of my CGI Course.


Comment on Re: Re: Re: Re: Often Overlooked OO Programming Guidelines
Select or Download Code

Log In?
Username:
Password:

What's my password?
Create A New User
Node Status?
node history
Node Type: note [id://317637]
help
Chatterbox?
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others surveying the Monastery: (6)
As of 2014-12-18 01:44 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?

    Is guessing a good strategy for surviving in the IT business?





    Results (41 votes), past polls