Merge commit '95aeb2ebae32a01ff79644daa523bda5d8552863' as 'third_party/lisp/alexandria' r/394

1 files changed, 18 insertions, 0 deletions

diff --git a/third_party/lisp/alexandria/arrays.lisp b/third_party/lisp/alexandria/arrays.lisp
new file mode 100644
index 000000000000..76c18791ad5f
--- /dev/null
+++ b/third_party/lisp/alexandria/arrays.lisp
@@ -0,0 +1,18 @@
+(in-package :alexandria)
+
+(defun copy-array (array &key (element-type (array-element-type array))
+                              (fill-pointer (and (array-has-fill-pointer-p array)
+                                                 (fill-pointer array)))
+                              (adjustable (adjustable-array-p array)))
+  "Returns an undisplaced copy of ARRAY, with same fill-pointer and
+adjustability (if any) as the original, unless overridden by the keyword
+arguments."
+ (let* ((dimensions (array-dimensions array))
+        (new-array (make-array dimensions
+                               :element-type element-type
+                               :adjustable adjustable
+                               :fill-pointer fill-pointer)))
+   (dotimes (i (array-total-size array))
+     (setf (row-major-aref new-array i)
+           (row-major-aref array i)))
+   new-array))