[cmucl-imp] Lexical closures and FUNCALLABLE-STANDARD-CLASS

Mark Cox markcox80 at gmail.com
Sun Jun 30 11:49:09 UTC 2013


Invoking a FUNCALLABLE-STANDARD-OBJECT which has the lexical closure created below as its function signals an error.

(defvar *a* nil)

(defclass something ()
  (:metaclass pcl:funcallable-standard-class))

(defun ensure-something (function)
  (let ((s (make-instance 'something)))
    (pcl:set-funcallable-instance-function s function)
    (setf *a* s)))

(let ((offset 1))
  (ensure-something #'(lambda (a)
			(+ offset a 3))))

(print (funcall *a* 3))
;; Should be 7.

Compiling and loading the above code (just loading is not enough) should produce the following error on CMUCL 20D x86 Darwin

Argument X is not a NUMBER: #<Closure Over Function "LET ((OFFSET 1))"
   [Condition of type SIMPLE-TYPE-ERROR]


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