Re: [pro] [Q] introspecting setf expanders

Pascal Costanza wrote:

Just guessing: If you see that the writer form is a funcall to a setf function, you can then check with fboundp if such a function actually exists. This is probably a bit shaky, but maybe good enough for practical purposes?

Good idea. To be more precise:

- if the writer form is something else than (FUNCALL #'(SETF FOO) ...) then there is a defsetf going on (it even takes precedence over a potential setf function).

- if the writer form is (FUNCALL #'(SETF FOO) ...) and that function is bound, then there is a setf function going on but no defsetf.

- otherwise, there is no writer at all.

I think this might just work.