NetNews Usenet Archive 1993 #1/NN_1993_1.iso/spool/comp/lang/cplus/19052

Text File | 1993-01-12 | 1.6 KB | 36 lines

Newsgroups: comp.lang.c++
Path: sparky!uunet!zaphod.mps.ohio-state.edu!howland.reston.ans.net!paladin.american.edu!darwin.sura.net!udel!rochester!rocksanne!news
From: [e-mail] (Jim Heliotis)
Subject: Re: Callbacks in C++
Message-ID: <[e-mail]>
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Organization: Xerox Corporation, Webster NY
References: <rmartin.726677907@thor>
Date: Tue, 12 Jan 1993 14:17:28 GMT
Lines: 23

In article 726677907@thor, [e-mail] (Bob Martin) writes:
>
>If you are designing a class library, you don't generally want to
>provide callbacks to your users.  Instead, you want to provide them
>with interfaces that they can use to receive information from you.
>These interfaces are abstract classes.  Pure virtual functions are
>declared which allow information to be passed from your class library
>to user objects derived from the abstract classes.  The users can
>implement the derivatives of the pure virtuals as they see fit.
>

That sounds like a callback to me, especially if something else in the
library calls the base class's pure virtual function.  I think it's
just a question of semantics.

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