I've recently been writing Perl objects until they come out of my ears. This has meant a great deal of re-reading of Mr Conways book, and a lot of soul-searching as to which aspects to keep and which are over-engineering for the requirements and the platform.

Since Perl's implementation of OO is commonly used with a hash, one hash for a class and all it's 'parents'. To avoid collision between names of inherited attributes a namespace is defined for each package and prepended to the attributes of an object. This is a poor summary of section 6.2.6 of OO Perl by Damian Donway.

Well it set me to thinking, that since I was brought up believing all properties of an object should be viewed through accessor methods, and altered through mutator methods, one way of achieving this was to slap on a long namespace to stop people tampering, it seemed a little more dictatorial than the '_' affordance, although I stuck to that too. 

$object->{_id};
$object->{_private_property_of_template_called_id_leave_it_be};

# Both could then have an accessor method, respectively
sub get_id () { $_[0]->{_id} }
sub get_id () { $_[0]->{ _private_property_of_template_called_id_leave
+_it_be
 } }

# And each would be called 
$object->get_id();

[download]

My reasoning being, the the major reason for people using the properties rather than the accessors, which might perform other duties, was mis-placed laziness.

Obviously, I hope, you can see that I've exagerated the length of the property, but does this makes sense to use? I really am in two minds as to whether this is a good thing, so I thought I'd post it here as people have some pretty strong views on OO...

--

Brother Frankus.

¤

In reply to A new take on affordance. by frankus

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