From 4ff3e7352d407e9da3ddd25408d5617055ca8c5a Mon Sep 17 00:00:00 2001
From: Jean-Paul Pelteret <jppelteret@gmail.com>
Date: Fri, 13 Jul 2018 12:03:06 +0200
Subject: [PATCH] Extend template specialisations for intermediate AD number
 types.

Its not likely, but it might be possible that in some complex chain of
operations we're left with one of these intermediates that needs to be
operated on or used. If this is the case then having these
specialisations facilitate the driver and helper classes to function
with these number types.
---
 .../differentiation/ad/sacado_number_types.h  | 21 +++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/include/deal.II/differentiation/ad/sacado_number_types.h b/include/deal.II/differentiation/ad/sacado_number_types.h
index 9c4adea987..8781865c5f 100644
--- a/include/deal.II/differentiation/ad/sacado_number_types.h
+++ b/include/deal.II/differentiation/ad/sacado_number_types.h
@@ -883,6 +883,16 @@ namespace Differentiation
     {};
 
 
+    template <typename NumberType>
+    struct is_sacado_dfad_number<
+      NumberType,
+      typename std::enable_if<std::is_same<
+        NumberType,
+        Sacado::Fad::Expr<typename NumberType::value_type>>::value>::type>
+      : std::true_type
+    {};
+
+
     template <typename NumberType>
     struct is_sacado_rad_number<
       NumberType,
@@ -894,6 +904,17 @@ namespace Differentiation
     {};
 
 
+    template <typename NumberType>
+    struct is_sacado_rad_number<
+      NumberType,
+      typename std::enable_if<std::is_same<
+        NumberType,
+        Sacado::Rad::ADvari<Sacado::Fad::DFad<
+          typename NumberType::ADVari::scalar_type>>>::value>::type>
+      : std::true_type
+    {};
+
+
     template <typename NumberType>
     struct is_sacado_number<
       NumberType,
-- 
2.39.5