Re: Porting from Modula-2 to Ada

["Robert I. Eachus" <rieachus@attbi.com>]

> I do not remember a mention of a subset of Modula-2, but if he mentioned
> it, then it might be described in the study examining Pascal; C; Ada 83;
> Modula-2; and assemblies he referred to for one of his tables."

> From "The choice of computer languages for use in safety-critical
> systems" by W.J. Cullyer, S.J. Goodenough [what a surname!] and
> B.A. Wichmann on pages 51 to 58 of the IEE's March 1991 Volume 6 Number 2
> issue of "Software Engineering Journal"...

Brian Wichmann and John Goodenough were both heavily involved in the 
development of Ada 83 and Ada 95.  John also did a lot of work on Rate 
monotonic scheduling.  But that is John B. Goodenough, I don't know if 
S. J. is one of his children.

Brain has also done a lot of work on SPARK a safety-critical subset of 
Ada and what is known as the Ravescar Profile for tasking in embedded 
Ada systems.

I am not in a position to judge whether SPARK is the best subset 
language for safety-critical applications, but it is probably one of the 
most popular across all possible base languages.  (I tend to prefer a 
richer subset with machine language level review tools...)