I just stumbled upon this and I need confirmation.

You cannot do anything like this, can you?

(defstruct foo x)

(deftype foo-with-x (x) (satisfies 'foo-with-x-p)) ; No `x'!

(typep (make-foo :x 42) '(foo-with-x 42))

I.e., there is no way to pass the x to foo-with-x-p, is there?

All the best

Marco Antoniotti, Professor tel. +39 - 02 64 48 79 01
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