+(defun null-lexenv-p (lexenv)
+ (equalp (coerce-to-lexenv lexenv) (make-null-lexenv)))
+
+(defun print-lexenv (lexenv stream level)
+ (if (null-lexenv-p lexenv)
+ (print-unreadable-object (lexenv stream)
+ (write-string "NULL-LEXENV" stream))
+ (default-structure-print lexenv stream level)))
+