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Wait, wait, wait...'bless only once'...?? Um...I don't think so...

Each object's creation code must return a blessed reference to indicate that the returned 'object' is now part of that class (has been blessed into that class) -- meaning that the reference can be now called on any method in the new class.

W/o the blessing @ each level, you couldn't use the reference to call subclass methods, as it's not a pointer of any class (yet), until it's done being initialized into that class.

So something like 'cacheable' wouldn't be able to use the 'path' method of 'url' to derive a cacheable's path. Example:

package url (methods:new 'host' 'path') package url::cacheable sub new { $package=shift; $up=new url(@_); # host & path passed in args $up->path($cpath) if ($cpath=_canonical_path($up->path)) ne $path; bless $up, $package; }
So when $up comes back from 'new url', it's a ref to a url-blessed object and is used as such. But not until the path of the 'url' object has been tested as (and possibly set to) '_canonical_path', is it suitable to be blessed as a 'cachceable' object.

Am I missing something?


In reply to Re^2: blessed confusion by perl-diddler
in thread blessed confusion by perl-diddler

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