Re: SETF for functions returning multiple values.

On 9 Jun 2026, at 11:19, Madhu (as enometh at meer dot net) <[email protected]> wrote:
> I'd just use a cons.  

In this case the values were handler and right delimiter and the interface needed to be compatible with an earlier one where delimiters always matched (so it supported syntax like #D|...| only).

Adding a second value seemed like it would enable an entirely compatible interface which exported no new symbols.  But it doesn't, because you want to be able to know what delimiter pairs exist in a handler table.

I did think about exposing that as an alist but that then means you have to answer questions about duplicate entries, whether modifying the alist modifies the behaviour, whether it's legal to do that & so on.  So it now has an accessor and a mapping function (with the restrictions of maphash, which is what it in fact is inside).

--tim

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