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From: dxf <dxforth@gmail.com>
Newsgroups: comp.lang.forth
Subject: Re: EXECUTE implementation in native-code systems
Date: Mon, 17 Mar 2025 20:34:19 +1100
Organization: i2pn2 (i2pn.org)
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On 17/03/2025 5:12 pm, Anton Ertl wrote:
> dxf <dxforth@gmail.com> writes:
>> Would you agree 'nest-sys' are peculiar to colon definitions.  That
>> EXECUTE is a different class of function.  It's not doing a 'call'
>> as such and not leaving anything on the 'return stack'?
> 
> That's certainly the case for threaded-code implementations.
> 
> For native-code implementations the implementation of EXECUTE is
> usually an indirect call; sometimes an indirect tail-call, i.e. a
> jump.
> ...

Yes.  Also for optimizing native-code it may be 'xt EXECUTE' itself will
be optimized away.  Since the Standard doesn't specify a nest-sys in
relation to EXECUTE we can safely assume there isn't one?  If not, when
would it be an issue?