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Re: PDD 2, vtables

From:
David Mitchell
Date:
February 7, 2001 09:54
Subject:
Re: PDD 2, vtables
Message ID:
200102071754.RAA10216@tiree.fdgroup.co.uk
> > > ++ and -- are already slightly messy in perl5
> > > 
> > > pp_preinc, pp_postinc, pp_predec and pp_postdec live in with all the ops.
> > > They know how to increment and decrement integers that don't overflow,
> > > and call routines in sv.c to increment and decrement anything else.
> > > 
> > > Actually, this nearly provides a divide between values and operators
> > > that has been suggested, with the speed up hack for the common case.
> > 
> > I'm not sure I follow you. What is the "this" in "this nearly provides a
> > divide"?
> 
> this example.
> I think the "nearly" probably should go.
> Maybe I should have written "++ and -- in perl5 provides an example of a
> (nearly clean) divide between operator and value

Well, many of the vtable methods are operator-ish rather than value-ish,
presumably on the grounds of efficiency. A pure 'value' vtable wouldnt
have add(), concatenate() etc. Whihc leads me back to: I'm not sure
whether you are in favour of, or oppose, += etc being vtable methods.
 
> > Confused of Sheffield.
> 
> Hmm. Yes. I'm confused too.
> 
> Confused of Newcastle

Fancy swapping some cutlery for some Brown Ale? ;-)

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