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Re: no constants please

This page is part of the web mail archives of SRFI 50 from before July 7th, 2015. The new archives for SRFI 50 contain all messages, not just those from before July 7th, 2015.

Richard Kelsey <kelsey@xxxxxxx> writes:

> No, (a) he gave a reason why you might have multiple C values
> representing Scheme's #F.  He didn't give a reason why
> you would allocate those values on the fly (as opposed to
> creating them when the corresponding heap is created).

I gave that as an explanation for why you can't use == in place of

Moreover, this also shows why you want SCHEME_FALSE to be a function:
so you can return a better value for #f than some global default; you
want a heap-specific or thread-specific one.

I also agree with Tom Lord's point that read-barrier GC strategies way
want to require an eq? other than ==.

> And (b), my point is not that there are no advantages for
> doing so, but that any benefit from it would be outweighed
> by associated costs.

What costs on earth does it impose on the FFI?