Path: news.daimi.aau.dk!news From: Peter von der Ahe Newsgroups: comp.lang.beta Subject: Re: Redefinition of attributes in BETA (Q) Date: 09 Oct 1996 21:01:05 +0200 Organization: DAIMI, Computer Science Dept. of Aarhus Univ. Lines: 36 Sender: pahe@indium.daimi.aau.dk Message-ID: References: <325B9F88.1C10@informatik.uni-stuttgart.de> NNTP-Posting-Host: indium.daimi.aau.dk X-Newsreader: Gnus v5.2.40/Emacs 19.30 >>>>> "BH" == Bernd Holzmueller writes: BH> Is it possible to give a completely new attribute definition in a BH> subpattern for a non-virtual attribute? And, if so, does the BH> subpattern then contain both attribute definitions (like in BH> SIMULA)? And, if so, how can one access the overriden attribute? ORIGIN '~beta/basiclib/v1.5/betaenv'; --PROGRAM: descriptor-- (# V: (# A: @Integer; do 3->a; INNER #); W: V (# A: @Integer; do 4->a;a->putInt;newline; THIS(V).a->putInt;newline; #) do W #) In the Mjolner BETA implementation the above program writes 4 3 on stdout, so the Mjolner implementation allows you to override an attribute. I'm not sure whether this is semantically correct or not. All the textbook references I can find kindly ignore the topic when discussing qualification. /Peter -- Peter von der Ahe Ny Munkegade 101,1 tv, DK 8000 Aarhus C,Denmark Phone: +45 8613 2634, E-mail: pahe@daimi.aau.dk www: http://www.daimi.aau.dk/~pahe/