+(defun maybe-call-ctor (class initargs)
+ (flet ((frob-initargs (ctor)
+ (do ((ctail (ctor-initargs ctor))
+ (itail initargs)
+ (args nil))
+ ((or (null ctail) (null itail))
+ (values (nreverse args) (and (null ctail) (null itail))))
+ (unless (eq (pop ctail) (pop itail))
+ (return nil))
+ (let ((cval (pop ctail))
+ (ival (pop itail)))
+ (if (constantp cval)
+ (unless (eql cval ival)
+ (return nil))
+ (push ival args))))))
+ (dolist (ctor (plist-value class 'ctors))
+ (when (eq (ctor-state ctor) 'optimized)
+ (multiple-value-bind (ctor-args matchp)
+ (frob-initargs ctor)
+ (when matchp
+ (return (apply ctor ctor-args))))))))
+