From bb860f3464abbe116cbb8267cef31d873bf4dba0 Mon Sep 17 00:00:00 2001
From: Wolfgang Bangerth <bangerth@colostate.edu>
Date: Mon, 24 Jan 2022 11:34:45 -0700
Subject: [PATCH] Minor edits to type traits classes.

---
 include/deal.II/lac/la_parallel_vector.h  |  8 ++---
 include/deal.II/lac/precondition.h        | 36 +++++++++++------------
 include/deal.II/matrix_free/type_traits.h | 16 +++++-----
 3 files changed, 30 insertions(+), 30 deletions(-)

diff --git a/include/deal.II/lac/la_parallel_vector.h b/include/deal.II/lac/la_parallel_vector.h
index 09794599bf..44d0161fbf 100644
--- a/include/deal.II/lac/la_parallel_vector.h
+++ b/include/deal.II/lac/la_parallel_vector.h
@@ -1899,7 +1899,7 @@ namespace internal
 
       public:
         static const bool value =
-          !std::is_same<bool, decltype(detect(std::declval<T>()))>::value;
+          !std::is_same<decltype(detect(std::declval<T>())), bool>::value;
       };
 
       // A helper type-trait that leverage SFINAE to figure out if type T has
@@ -1917,7 +1917,7 @@ namespace internal
 
       public:
         static const bool value =
-          !std::is_same<bool, decltype(detect(std::declval<T>()))>::value;
+          !std::is_same<decltype(detect(std::declval<T>())), bool>::value;
       };
 
       // A helper type-trait that leverage SFINAE to figure out if type T has
@@ -1935,7 +1935,7 @@ namespace internal
 
       public:
         static const bool value =
-          !std::is_same<bool, decltype(detect(std::declval<T>()))>::value;
+          !std::is_same<decltype(detect(std::declval<T>())), bool>::value;
       };
 
       // A helper type-trait that leverage SFINAE to figure out if type T has
@@ -1954,7 +1954,7 @@ namespace internal
 
       public:
         static const bool value =
-          !std::is_same<bool, decltype(detect(std::declval<T>()))>::value;
+          !std::is_same<decltype(detect(std::declval<T>())), bool>::value;
       };
 
       // Used for (Trilinos/PETSc)Wrappers::SparseMatrix
diff --git a/include/deal.II/lac/precondition.h b/include/deal.II/lac/precondition.h
index 7e292ccf91..ef2383fecd 100644
--- a/include/deal.II/lac/precondition.h
+++ b/include/deal.II/lac/precondition.h
@@ -536,13 +536,13 @@ namespace internal
 
       template <typename U>
       static decltype(
-        std::declval<U const>().Tvmult(std::declval<VectorType &>(),
+        std::declval<const U>().Tvmult(std::declval<VectorType &>(),
                                        std::declval<const VectorType &>()))
       detect(const U &);
 
     public:
       static const bool value =
-        !std::is_same<bool, decltype(detect(std::declval<T>()))>::value;
+        !std::is_same<decltype(detect(std::declval<T>())), bool>::value;
     };
 
     template <typename T, typename VectorType>
@@ -557,13 +557,13 @@ namespace internal
 
       template <typename U>
       static decltype(
-        std::declval<U const>().step(std::declval<VectorType &>(),
+        std::declval<const U>().step(std::declval<VectorType &>(),
                                      std::declval<const VectorType &>()))
       detect(const U &);
 
     public:
       static const bool value =
-        !std::is_same<bool, decltype(detect(std::declval<T>()))>::value;
+        !std::is_same<decltype(detect(std::declval<T>())), bool>::value;
     };
 
     template <typename T, typename VectorType>
@@ -578,14 +578,14 @@ namespace internal
 
       template <typename U>
       static decltype(
-        std::declval<U const>().step(std::declval<VectorType &>(),
+        std::declval<const U>().step(std::declval<VectorType &>(),
                                      std::declval<const VectorType &>(),
                                      std::declval<const double>()))
       detect(const U &);
 
     public:
       static const bool value =
-        !std::is_same<bool, decltype(detect(std::declval<T>()))>::value;
+        !std::is_same<decltype(detect(std::declval<T>())), bool>::value;
     };
 
     template <typename T, typename VectorType>
@@ -600,13 +600,13 @@ namespace internal
 
       template <typename U>
       static decltype(
-        std::declval<U const>().Tstep(std::declval<VectorType &>(),
+        std::declval<const U>().Tstep(std::declval<VectorType &>(),
                                       std::declval<const VectorType &>()))
       detect(const U &);
 
     public:
       static const bool value =
-        !std::is_same<bool, decltype(detect(std::declval<T>()))>::value;
+        !std::is_same<decltype(detect(std::declval<T>())), bool>::value;
     };
 
     template <typename T, typename VectorType>
@@ -621,14 +621,14 @@ namespace internal
 
       template <typename U>
       static decltype(
-        std::declval<U const>().Tstep(std::declval<VectorType &>(),
+        std::declval<const U>().Tstep(std::declval<VectorType &>(),
                                       std::declval<const VectorType &>(),
                                       std::declval<const double>()))
       detect(const U &);
 
     public:
       static const bool value =
-        !std::is_same<bool, decltype(detect(std::declval<T>()))>::value;
+        !std::is_same<decltype(detect(std::declval<T>())), bool>::value;
     };
 
     template <typename T, typename VectorType>
@@ -643,14 +643,14 @@ namespace internal
 
       template <typename U>
       static decltype(
-        std::declval<U const>().Jacobi_step(std::declval<VectorType &>(),
+        std::declval<const U>().Jacobi_step(std::declval<VectorType &>(),
                                             std::declval<const VectorType &>(),
                                             1.0))
       detect(const U &);
 
     public:
       static const bool value =
-        !std::is_same<bool, decltype(detect(std::declval<T>()))>::value;
+        !std::is_same<decltype(detect(std::declval<T>())), bool>::value;
     };
 
     template <typename T, typename VectorType>
@@ -665,14 +665,14 @@ namespace internal
 
       template <typename U>
       static decltype(
-        std::declval<U const>().SOR_step(std::declval<VectorType &>(),
+        std::declval<const U>().SOR_step(std::declval<VectorType &>(),
                                          std::declval<const VectorType &>(),
                                          1.0))
       detect(const U &);
 
     public:
       static const bool value =
-        !std::is_same<bool, decltype(detect(std::declval<T>()))>::value;
+        !std::is_same<decltype(detect(std::declval<T>())), bool>::value;
     };
 
     template <typename T, typename VectorType>
@@ -687,14 +687,14 @@ namespace internal
 
       template <typename U>
       static decltype(
-        std::declval<U const>().SSOR_step(std::declval<VectorType &>(),
+        std::declval<const U>().SSOR_step(std::declval<VectorType &>(),
                                           std::declval<const VectorType &>(),
                                           1.0))
       detect(const U &);
 
     public:
       static const bool value =
-        !std::is_same<bool, decltype(detect(std::declval<T>()))>::value;
+        !std::is_same<decltype(detect(std::declval<T>())), bool>::value;
     };
 
     template <typename T, typename VectorType>
@@ -2632,8 +2632,8 @@ namespace internal
       // detector, otherwise SFINAE let's it work with the more general first
       // one that is bool
       static const bool value =
-        !std::is_same<bool,
-                      decltype(detect(std::declval<MatrixType>()))>::value &&
+        !std::is_same<decltype(detect(std::declval<MatrixType>())),
+                      bool>::value &&
         std::is_same<PreconditionerType, DiagonalMatrix<VectorType>>::value &&
         std::is_same<
           VectorType,
diff --git a/include/deal.II/matrix_free/type_traits.h b/include/deal.II/matrix_free/type_traits.h
index d2b6170976..cdb9e3f728 100644
--- a/include/deal.II/matrix_free/type_traits.h
+++ b/include/deal.II/matrix_free/type_traits.h
@@ -51,7 +51,7 @@ namespace internal
     // and its return type will be the same as local_element(),
     // that we expect to be T::value_type
     template <typename U>
-    static decltype(std::declval<U const>().local_element(0))
+    static decltype(std::declval<const U>().local_element(0))
     detect(const U &);
 
   public:
@@ -129,13 +129,13 @@ namespace internal
     detect(...);
 
     template <typename U>
-    static decltype(std::declval<U const>().partitioners_are_compatible(
+    static decltype(std::declval<const U>().partitioners_are_compatible(
       std::declval<Utilities::MPI::Partitioner>()))
     detect(const U &);
 
   public:
     static const bool value =
-      std::is_same<bool, decltype(detect(std::declval<T>()))>::value;
+      std::is_same<decltype(detect(std::declval<T>())), bool>::value;
   };
 
   // We need to have a separate declaration for static const members
@@ -153,7 +153,7 @@ namespace internal
     detect(...);
 
     template <typename U>
-    static decltype(std::declval<U const>().begin())
+    static decltype(std::declval<const U>().begin())
     detect(const U &);
 
   public:
@@ -176,7 +176,7 @@ namespace internal
     detect(...);
 
     template <typename U>
-    static decltype(std::declval<U const>().shared_vector_data())
+    static decltype(std::declval<const U>().shared_vector_data())
     detect(const U &);
 
   public:
@@ -228,12 +228,12 @@ namespace internal
     detect(...);
 
     template <typename U>
-    static decltype(std::declval<U const>().update_ghost_values_start(0))
+    static decltype(std::declval<const U>().update_ghost_values_start(0))
     detect(const U &);
 
   public:
     static const bool value =
-      !std::is_same<bool, decltype(detect(std::declval<T>()))>::value;
+      !std::is_same<decltype(detect(std::declval<T>())), bool>::value;
   };
 
   // We need to have a separate declaration for static const members
@@ -257,7 +257,7 @@ namespace internal
 
   public:
     static const bool value =
-      !std::is_same<bool, decltype(detect(std::declval<T>()))>::value;
+      !std::is_same<decltype(detect(std::declval<T>())), bool>::value;
   };
 
   // We need to have a separate declaration for static const members
-- 
2.39.5