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marcoheisig/typed-cells.lisp

Last active June 20, 2020 06:34
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A possible safe implementation of typed cells for SICL.
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typed-cells.lisp
(defun make-function-cell (value)
(check-type value function)
(values
(lambda () value)
(lambda (new-value)
(check-type new-value function)
(setf value new-value))))
;; In order to make typed cells as fast as cons cells,
;; the compiler has to be able to inline the first value returned by
;; MAKE-FUNCTION-CELL even though it is a closure.
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