`(unless ,expr
(%failed-aver ,(let ((*package* (find-package :keyword)))
(format nil "~S" expr)))))
-(defun %failed-aver (expr)
- (error "~@<failed AVER: ~2I~_~S~:>" expr))
+(defun %failed-aver (expr-as-string)
+ (error "~@<failed AVER: ~2I~_~S~:>" expr-as-string))
\f
;;;; utilities for two-VALUES predicates