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Above shows my Mail::Box objects. Close observers see the difference between the Mail::Box-approach and the Mail::Folder set-up. The specialisation is broken-up further, till now without replacing the existing modules.

The Mail::Box::Message extends the MIME::Entity for instance by containing a sequence-number within the folder, which is not a habit of a basic message. The Mail::Box::Mbox::Message extends a normal folder message even further, containing information about where in the folder-file, the message was found. This is not the case for Mail::Box::MH::Message's, where each message has a file-name related to it.

One of the main targets of OO-design is to find characteristic knowledge and functionality, and split it into different objects, in stead of throwing all on one huge pile.

Inheritance To Test or Not to Test

Created by Mark Overmeer with PPresenter on 5 August 2001