0.7.12.30

[sbcl.git] / src / code / late-type.lisp

diff --git a/src/code/late-type.lisp b/src/code/late-type.lisp
index ff52c67..5d3b845 100644 (file)
--- a/src/code/late-type.lisp
+++ b/src/code/late-type.lisp
@@ -631,12 +631,13 @@
                              :complex-arg1 :complex-subtypep-arg1))))
 
 ;;; Just parse the type specifiers and call CSUBTYPE.
-(defun sb!xc:subtypep (type1 type2)
+(defun sb!xc:subtypep (type1 type2 &optional environment)
   #!+sb-doc
   "Return two values indicating the relationship between type1 and type2.
   If values are T and T, type1 definitely is a subtype of type2.
   If values are NIL and T, type1 definitely is not a subtype of type2.
   If values are NIL and NIL, it couldn't be determined."
+  (declare (ignore environment))
   (csubtypep (specifier-type type1) (specifier-type type2)))
 
 ;;; If two types are definitely equivalent, return true. The second
@@ -836,7 +837,7 @@
 (defun accumulate1-compound-type (type types %compound-type-p simplify2)
   (declare (type ctype type))
   (declare (type (vector ctype) types))
-  (declare (type function simplify2))
+  (declare (type function %compound-type-p simplify2))
   ;; Any input object satisfying %COMPOUND-TYPE-P should've been
   ;; broken into components before it reached us.
   (aver (not (funcall %compound-type-p type)))
@@ -1200,12 +1201,23 @@
   (declare (ignore type1 type2))
   (values nil nil))
 
-(!define-type-method (hairy :simple-intersection2 :complex-intersection2)
+(!define-type-method (hairy :simple-intersection2) 
                     (type1 type2)
   (if (type= type1 type2)
       type1
       nil))
 
+(!define-type-method (hairy :complex-intersection2)
+                    (type1 type2)
+  (aver (hairy-type-p type2))
+  (let ((hairy-type-spec (type-specifier type2)))
+    (if (and (consp hairy-type-spec)
+            (eq (car hairy-type-spec) 'not))
+       (if (csubtypep type1 (specifier-type (cadr hairy-type-spec)))
+           *empty-type*
+           nil)
+       nil)))
+       
 (!define-type-method (hairy :simple-=) (type1 type2)
   (if (equal (hairy-type-specifier type1)
             (hairy-type-specifier type2))
@@ -2413,8 +2425,12 @@
 (!define-type-class cons)
 
 (!def-type-translator cons (&optional (car-type-spec '*) (cdr-type-spec '*))
-  (make-cons-type (specifier-type car-type-spec)
-                 (specifier-type cdr-type-spec)))
+  (let ((car-type (specifier-type car-type-spec))
+       (cdr-type (specifier-type cdr-type-spec)))
+    (if (or (eq car-type *empty-type*)
+           (eq cdr-type *empty-type*))
+       *empty-type*
+       (make-cons-type car-type cdr-type))))
  
 (!define-type-method (cons :unparse) (type)
   (let ((car-eltype (type-specifier (cons-type-car-type type)))