On Mar 15, 12:21 am, "Ed" <nos...@[EMAIL PROTECTED]
> wrote:
> "Mark W. Humphries" <m...@[EMAIL PROTECTED]
> wrote in
messagenews:68cfbbe8-8cf3-461d-99b5-bf34f619cb66@[EMAIL PROTECTED]
>
> > On Mar 14, 9:43 am, "Ed" <nos...@[EMAIL PROTECTED]
> wrote:
> > ...
> > I've named one of the two conditional exits WHEN
> >http://wiki.forthfreak.net/index.cgi?TerseControlStructures,
I don't
> > know is this is common usage though:
>
> > : example1 full? unless eat-lunch ;
> > : example2 hungry? when eat-lunch ;
>
> Interesting. I hadn't seen that before.
>
> I don't know that there's been common use of the name WHEN
> in forth. I checked several popular '94 forths before using it. I
> saw WHEN used once or twice in control structure articles early
> on in FD but nothing seems to have come of them.
>
> I chose WHEN because it exists in control structure statements
> of other languages and therefore would be familiar to users in
> that context. Similarly with COND.
I'd caution against the use if a word like WHEN in this context. In
normal English usage WHEN is the time at which something happens. It
has connotations of asynchronous processing, perhaps as an interrupt
routine. As in
: wait-interrupt-****t ( ****t# -- )
****t-wait when ... some async actvity ... end-when ;
(wait-interrupt-****t returns immediately, but the WHEN END-WHEN body
is run asynchronously.)
WHEN doesn't imply some form of immediate inline IF test to me.
--
Regards
Alex McDonald
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