implemented factorial calculated by compiler.

[[Imported from SVN: r4330]]

common/misc.hh

@@ -57,7 +57,7 @@ namespace Dune {
     enum { power = (m * Power_m_p<m,p-1>::power ) };
   };
 
-  // end of recursion via specialization
+  //! end of recursion via specialization
   template <int m>
   struct Power_m_p< m , 0>
   {
@@ -65,6 +65,22 @@ namespace Dune {
     enum { power = 1 };
   };
 
+  //! Calculates the factorial of m at compile time
+  template <int m>
+  struct Factorial
+  {
+    //! factorial stores m!
+    enum { factorial = m * Factorial<m-1>::factorial };
+  };
+
+  //! end of recursion of factorial via specialization
+  template <>
+  struct Factorial<0>
+  {
+    // 0! = 1
+    enum { factorial = 1 };
+  };
+
   //********************************************************************
   //
   // generate filenames with timestep number in it