I really have to disagree with your first supposition. There is a world of difference between $obj->{field} and $obj->field(). In fact, the difference is one of the cornerstones of oo.
With the direct access, I have no control over the field. The consumer can store anything it it, squirrel away references to it, change the internal state of my object from a distance using those references, etc.
With the accessor, I have complete control over the field. I can validate changes to the field using any criteria I choose. I can change storage methods. I can manipulate the data internally. I can do anything I need to, without breaking the users code and without the user breaking my code.

UPDATE: It also removes an entire level of error prevention. There is no way to detect mistyped fieldnames. The following code fails silently bacause it is syntactically correct, and without accessors there is no mechanism to detect bad field names. 
   my $var = $obj->{field};
   $var = someManipulation($var);
   $obj->{feild}=$var;

[download]


-pete
"Worry is like a rocking chair. It gives you something to do, but it doesn't get you anywhere."

In reply to Re: Re: OO Getters/Setters by dreadpiratepeter
in thread OO Getters/Setters by theAcolyte

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