🚀 go-pugleaf

In article <1992Dec13.144549.24447@reed.edu> orpheus@reed.edu (P. Hawthorne) writes:
>From: orpheus@reed.edu (P. Hawthorne)
>Subject: The Member Function: Spawn Of Satan?
>Date: 13 Dec 92 14:45:49 GMT
>In Object C and Pascal, the member function reveals whether a given object
>is descended from a given class. I wonder if it is good or bad to use it.
>It seems un-structured. What would Djikstra say?
>
>When I use it, I invariably feel guilty. I worry that perhaps a seriously
>abstract class variable could formalize whatever notions are at work. Or I
>think that it is a kludge so that I can put off a total overhaul until I
>figure out how to work in the exceptional classes. That sort of thing.
>
>So then, am I just an OO-prude?
>
>Dumbfounded,
>Theus (orpheus@reed.edu)


As of today, I#ve found a very nice way to use the member() function. Say, 
we want something to do at the idle time -- update a clock on-screen, do 
some measuring from an external DVM, something the like. It turns out the 
clock never needs to be configured, while the external device needs this 
option (since there is more than one kind of external device You can connect 
to). Of course, the solution is a class

class TIdlingObject{}

which does all the idling behavior, such as scheduling idlers, executing 
them, and the like.

derived from this one are various subclasses -- say, TEditableIdlingObject 
and TFacelessIdlingObject.

The tricky part comes when You want the user to access instances of idling 
objects. You can easily build a list of TIdlingObjects, but the only way to 
exclude the TFacelessIdlingObjects from the list will be to call the member 
function -- which tells You if the object You look at is an 
TEditableIdlingObject.

So, leave the theroy aside and use it -- it's really useful.

-Christoph

P.S: Sorry about all that MacAppish names, but I'm used to...

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