Add RandomNumberGenerator adapter to base/rand_util.h

base/rand_util.h

Index: base/rand_util.h
diff --git a/base/rand_util.h b/base/rand_util.h
index 451a7d1c172cfe71e8176c4df405942a473e246d..699fc7fabbec89065ad3a4afe0146c524b050b0f 100644
--- a/base/rand_util.h
+++ b/base/rand_util.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2008 The Chromium Authors. All rights reserved.
+// Copyright (c) 2010 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
@@ -16,6 +16,13 @@ uint64 RandUint64();
 // Returns a random number between min and max (inclusive). Thread-safe.
 int RandInt(int min, int max);
 
+// Returns a random number in range [0, max).  Thread-safe.
+//
+// Note that this can be used as an adapter for std::random_shuffle():
+// Given a pre-populated |std::vector<int> myvector|, shuffle it as
+//   std::random_shuffle(myvector.begin(), myvector.end(), base::RandGenerator);
+uint64 RandGenerator(uint64 max);

[Paweł Hajdan Jr., 2010/08/30 18:09:02]

I think I'd prefer a RandomShuffle thing. The implementation seems to be small
enough to fit inline in case we need this for template reasons. However, if
Brett wouldn't like it, I'm fine with the current solution.

+
 // Returns a random double in range [0, 1). Thread-safe.
 double RandDouble();