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From: gardner@titan.tsd.arlut.utexas.edu (Don Gardner)
Newsgroups: comp.lang.ada
Subject: Types defining h/w r/o or w/o registers
Message-ID: <3949@titan.tsd.arlut.utexas.edu>
Date: 30 May 91 13:03:52 GMT
Reply-To: gardner@titan.tsd.arlut.utexas.edu (Donald Gardner)
Organization: Applied Research Labs, The University of Texas at Austin
List-Id: <comp.lang.ada>

Is there some way to define a type such that all variables of that
type can be only read or only written?  For instance, I have a type that
defines the status register of some peripheral which can only be 
read.  It would be best if the compiler could flag any assignments 
to variables of such a type as errors.

Is there some other means for commonly handling this problem?  The 
compiler being used is VADSWorks, if an implementation-defined solution
is required.