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From: Pat.Terry@p101.f4.n494.z5.fidonet.org (Pat Terry)
Newsgroups: comp.lang.modula2
Subject: Re: Implementing Abstract Lists
Message-ID: <459.26C1B329@puddle.fidonet.org>
Date: 9 Aug 90 21:43:56 GMT
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 > Umm, gee, Dave, maybe I'm missing the point, here, but isn't this where a 
 > variant record would come in real handy?  As in
 > 
 > TYPE
 >    ThingType = ( aThing, anotherThing, lastThing ) ;
 >    ItemType = RECORD
 >       CASE ThingType OF
 >          aThing:
 >             fields for a thing
 >             |
 >          anotherThing:
 >             fields for another thing
 >             |
 >          lastThing:
 >             fields for last thing
 >       END  (* case *)
 >    END ;
 > 
 > Maybe I just misunderstood your problem, but using the above definition, 
 > one copy of the "List" module would handle three widely different types of 
 > things.

Um, gee.  But if you wanted to add a few more things you'd have to rewrite the   
CASE variants statement and recompile lots and lots, maybe.  And change the   
CASE statements that would litter the code too.



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