(!begin-collecting-cold-init-forms)
-;;; Has the type system been properly initialized? (I.e. is it OK to
-;;; use it?)
-(defvar *type-system-initialized* #+sb-xc-host nil) ; (set in cold load)
-\f
;;;; representations of types
;;; A HAIRY-TYPE represents anything too weird to be described
(eq cdr-type *empty-type*))
*empty-type*
(%make-cons-type car-type cdr-type)))
+
+(defun cons-type-length-info (type)
+ (declare (type cons-type type))
+ (do ((min 1 (1+ min))
+ (cdr (cons-type-cdr-type type) (cons-type-cdr-type cdr)))
+ ((not (cons-type-p cdr))
+ (cond
+ ((csubtypep cdr (specifier-type 'null))
+ (values min t))
+ ((csubtypep *universal-type* cdr)
+ (values min nil))
+ ((type/= (type-intersection (specifier-type 'cons) cdr) *empty-type*)
+ (values min nil))
+ ((type/= (type-intersection (specifier-type 'null) cdr) *empty-type*)
+ (values min t))
+ (t (values min :maybe))))
+ ()))
+
\f
;;;; type utilities