Re: Stack vs stackless operation

anton@mips.complang.tuwien.ac.at (Anton Ertl) writes:

Paul Rubin <no.email@nospam.invalid> writes:

anton@mips.complang.tuwien.ac.at (Anton Ertl) writes:

!@ is now the nonatomic version.

>
Is the nonatomic one useful often?

>
Some numbers of uses in the Gforth image:
>
11 !@
3  atomic!@
66 +!
>

We've done without it all this time.

>
Sure, you can replace it with DUP @ >R ! R>.  Having a word for that
relieves the programmer of producing such a sequence (possibly with a
bug) and the reader of having to analyse what's going on here.

Another point: These 11 uses of non-atomic !@ used to be uses of the
slow atomic !@.  So even the slow atomic !@ was preferred by the
programmer to doing it with @, ! and stack manipulation.  In that
situation the non-atomic !@ provides the wanted capability without
incurring the atomic slowness.

- anton
--
M. Anton Ertl  http://www.complang.tuwien.ac.at/anton/home.html
comp.lang.forth FAQs: http://www.complang.tuwien.ac.at/forth/faq/toc.html
     New standard: https://forth-standard.org/
EuroForth 2023 proceedings: http://www.euroforth.org/ef23/papers/
EuroForth 2024 proceedings: http://www.euroforth.org/ef24/papers/