Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!wuarchive!usc!elroy.jpl.nasa.gov!decwrl!pa.dec.com!src.dec.com!Thomas Roemke <modula-3@uni-paderborn.de>
From: modula-3@uni-paderborn.de (Thomas Roemke)
Newsgroups: comp.lang.modula3
Subject: ASSERT vs. error message
Message-ID: <9104191257.AA10485@thor.uni-paderborn.de>
Date: 19 Apr 91 13:10:43 GMT
Lines: 30
To: m3
X-Mailer: ELM [version 2.3 PL11]



The program below contains an illegal default method value for p.
I expected to get an error message like ''default is incompatible with method type'',
but instead I got:
M3 runtime error, "Type.m3":473: ASSERT failed

Program /homes/thor/modula-3/m3_1.6/lib/m3/m3compiler got fatal signal 3.

Why are you using an ASSERT ?
Is the computation of ''is AB a supertype of A'' more complex than calculating A <: AB ? 

   MODULE bugtest EXPORTS Main;

   TYPE 
     A = OBJECT a: INTEGER METHODS p() := Pab END;
     AB = A OBJECT b: INTEGER END;

   PROCEDURE Pab(self: AB) = BEGIN END Pab;

   BEGIN
   END bugtest.


 Thomas

-- 
(*	Thomas Roemke, University of Paderborn, Germany 
	modula-3@uni-paderborn.de
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