Re: Beginners question: Abstract record extension

From: [at]} <robert.d.campbell{>
Date: Mon, 23 Sep 2002 15:28:24 +0000 (GMT)

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Hi

A related 'beginners' question:

In the code below I'm never quite sure what

x.key = y.key

does.
Does it compare all 11 CHARs, or only up to the 0X?

Personally I'm tempted to add a $ to one, or both, .key.
Is this necessary/efficient?

Incidently I think that a more useful error message to the
original problem is reported to the Log as well as the usual
compiler error marker in the Mod file.

Cheers
Robert Campbell


> Well, you have declared abstract methods in the abstract class, so you have
> to implement those methods in the "real" class:
>
> > StringNode = POINTER TO RECORD (Node)
> > key : ARRAY 11 OF CHAR;
> > END;

>
> PROCEDURE (x : StringNode) EqualTo* (y : Node) : BOOLEAN;
> BEGIN
> WITH y: StringNode DO
> RETURN x.key = y.key
> ELSE
> RETURN FALSE
> END
> END EqualTo;


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Received on Mon Sep 23 2002 - 17:28:24 UTC

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