X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fcode%2Farray.lisp;h=1df47c51f1fa5981add7329390e6e7843c5051b4;hb=395c461b58f0cd484c21913c1e075593c206b5c1;hp=7c2790ea48818db6fc31b17d4eb3c6f7458ad8b0;hpb=5758a6ab4c2d046b68b5409d13ed6b8d6199ba7c;p=sbcl.git

diff --git a/src/code/array.lisp b/src/code/array.lisp
index 7c2790e..1df47c5 100644
--- a/src/code/array.lisp
+++ b/src/code/array.lisp
@@ -476,6 +476,14 @@ of specialized arrays is supported."
 (defun data-vector-ref-with-offset (array index offset)
   (hairy-data-vector-ref array (+ index offset)))
 
+(declaim (ftype (function (array integer integer &optional t) nil) signal-invalid-array-index-error))
+(defun invalid-array-index-error (array index bound &optional axis)
+  (error 'invalid-array-index-error
+         :array array
+         :axis axis
+         :datum index
+         :expected-type `(integer 0 (,bound))))
+
 ;;; SUBSCRIPTS has a dynamic-extent list structure and is destroyed
 (defun %array-row-major-index (array subscripts
                                      &optional (invalid-index-error-p t))
@@ -497,11 +505,7 @@ of specialized arrays is supported."
             (declare (fixnum dim))
             (unless (and (fixnump index) (< -1 index dim))
               (if invalid-index-error-p
-                  (error 'simple-type-error
-                         :format-control "invalid index ~W~[~;~:; on axis ~:*~W~] in ~S"
-                         :format-arguments (list index axis array)
-                         :datum index
-                         :expected-type `(integer 0 (,dim)))
+                  (invalid-array-index-error array index dim axis)
                   (return-from %array-row-major-index nil)))
             (incf result (* chunk-size (the fixnum index)))
             (setf chunk-size (* chunk-size dim))))
@@ -509,14 +513,7 @@ of specialized arrays is supported."
               (length (length (the (simple-array * (*)) array))))
           (unless (and (fixnump index) (< -1 index length))
             (if invalid-index-error-p
-                ;; FIXME: perhaps this should share a format-string
-                ;; with INVALID-ARRAY-INDEX-ERROR or
-                ;; INDEX-TOO-LARGE-ERROR?
-                (error 'simple-type-error
-                       :format-control "invalid index ~W in ~S"
-                       :format-arguments (list index array)
-                       :datum index
-                       :expected-type `(integer 0 (,length)))
+                (invalid-array-index-error array index length)
                 (return-from %array-row-major-index nil)))
           index))))
 
@@ -1083,6 +1080,30 @@ of specialized arrays is supported."
       (setf (%array-dimension array 0) dimensions))
   (setf (%array-displaced-p array) displacedp)
   array)
+
+;;; User visible extension
+(declaim (ftype (function (array) (values (simple-array * (*)) &optional))
+                array-storage-vector))
+(defun array-storage-vector (array)
+  "Returns the underlying storage vector of ARRAY, which must be a non-displaced array.
+
+In SBCL, if ARRAY is a of type \(SIMPLE-ARRAY * \(*)), it is its own storage
+vector. Multidimensional arrays, arrays with fill pointers, and adjustable
+arrays have an underlying storage vector with the same ARRAY-ELEMENT-TYPE as
+ARRAY, which this function returns.
+
+Important note: the underlying vector is an implementation detail. Even though
+this function exposes it, changes in the implementation may cause this
+function to be removed without further warning."
+  ;; KLUDGE: Without TRULY-THE the system is not smart enough to figure out that
+  ;; the return value is always of the known type.
+  (truly-the (simple-array * (*))
+             (if (array-header-p array)
+                 (if (%array-displaced-p array)
+                     (error "~S cannot be used with displaced arrays. Use ~S instead."
+                            'array-storage-vector 'array-displacement)
+                     (%array-data-vector array))
+                 array)))
 
 ;;;; used by SORT