🚀 go-pugleaf

minyard@crchh453.bnr.ca (Corey Minyard) writes:

>However; will "Hello" be copied onto the stack?

Usually the string will have to be copied on the stack.
(Or, even worse, copied to a temporary object on the heap.)

>That seems very wasteful,
>but I don't see any other way around it.  I am writing an Oberon-2
>interpreter and I can't take this level of inefficiency.

This *really* is nasty.
Here come how the Oberon(-2)-compiler I use (Amiga-Oberon) solves the
problem:
there are Compiler-options that have a certain syntax and are put into
comments. This options allows to influence the creation of code in different
ways. One is to avoid the copying of ARRAY-parameters. If this is used in
a certain procedure, this procedure, of course, may not change this parameter.

Example:

    PROCEDURE PrintString(s : ARRAY OF CHAR); (* $CopyArrays- *)
    
This does exactly what you want and is still portable Oberon.
(I still think it's a bit ugly, since it somehow reminds me
of Turbo-Pascal...)

Another solution would be to make to Compiler intelligent enough to see that
the ARRAY ist not changed in the procedure and then chose this option 
automatically.

Martin
-- 
  Martin Horneffer - maho@dfv.rwth-aachen.de;
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