[llvm] r216709 - Add conversion constructor to convert ArrayRef<T*> to ArrayRef<const T*>. Reviewed with Chandler and David Blaikie.

[Craig Topper]

Author: ctopper
Date: Fri Aug 29 01:01:43 2014
New Revision: 216709

URL: http://llvm.org/viewvc/llvm-project?rev=216709&view=rev
Log:
Add conversion constructor to convert ArrayRef<T*> to ArrayRef<const T*>. Reviewed with Chandler and David Blaikie.

Modified:
    llvm/trunk/include/llvm/ADT/ArrayRef.h

Modified: llvm/trunk/include/llvm/ADT/ArrayRef.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/ADT/ArrayRef.h?rev=216709&r1=216708&r2=216709&view=diff
==============================================================================
--- llvm/trunk/include/llvm/ADT/ArrayRef.h (original)
+++ llvm/trunk/include/llvm/ADT/ArrayRef.h Fri Aug 29 01:01:43 2014
@@ -104,6 +104,14 @@ namespace llvm {
       Length(Vec.size()) {}
 #endif
 
+    /// Construct an ArrayRef<const T*> from ArrayRef<T*>. This uses SFINAE to
+    /// ensure that only ArrayRefs of pointers can be converted.
+    template <typename U>
+    ArrayRef(const ArrayRef<U *> &A,
+             typename std::enable_if<
+                 std::is_convertible<U *const *, T const *>::value>::type* = 0)
+      : Data(A.data()), Length(A.size()) {}
+
     /// @}
     /// @name Simple Operations
     /// @{