[Oberon] Re (2): Porting S3 / V4 Oberon

[peter at easthope.ca]

From:	Andreas Pirklbauer andreas_pirklbauer at yahoo.com
Date:	Sun Jan 3 03:59:16 CET 2021
> Adding back EXIT, RETURN, LOOP, etc, to the modified compiler would 
> certainly be doable.

Thanks for stating that Andreas.  It strikes me as the most optimistic 
sentence in the mailing list in recent months.  Maybe in a year or 
more!   

> ... just too many small, subtle differences ... 
> You might think that it’s straightforward, but it wasn’t, at 
> least not in a single-pass compiler (need for fixups for method 
> tables, etc).

I accept that absolutely.  "Devil is in the details."  True in any 
worthwhile project.

One practical question I can't suppress.  Are the three, EXIT, LOOP 
and RETURN advisable or required? In my very limited experience, 
removing LOOP is relatively painless.  What  about tolerating RETURN 
and EXIT but not LOOP?  My knowledge is inadequate to judge the 
tradeoff.

> But one would really need a clear motivation for doing all this 
> work. 

In my understanding there are two ways to have the old software in the 
new system: (1) change a large mass of software and make the new 
system with the new compiler in one shot. (2) Add comlexity to the new 
compiler; then change the mass of software incrementally.

Of course (2) is more appealing to the more naive (me).  I and others 
can help with smaller changes.  

Judging the tradeoff between (1) and (2) is for qualified people.  
Definitely beyond my qualification.

Regards,                                      ... P. L.




-- 
Tel: +1 604 670 0140            Bcc: peter at easthope. ca