// -*- tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- // vi: set et ts=4 sw=2 sts=2: #ifndef DUNE_COMMON_FORLOOP_HH #define DUNE_COMMON_FORLOOP_HH #include <dune/common/static_assert.hh> namespace Dune { /** \class ForLoop * @brief A static loop using TMP * * The ForLoop takes a * \code template<int i> class Operation * template argument with a static apply method * which is called for i=first...last (first<=last are int template arguments). * A specialization for class template class Operation for i=first * or i=last is not required. The class Operation must provide a * static void function apply(...). Arguments (as references) * can be passed through the ForLoop to this function * (up to 5 at the moment). * * It is possible to pass a subclass to the ForLoop * (since no specialization is needed). * Example of usage: * template <class Foo> * struct A * { * template <int i> * struct Operation * { * template <class T> * static void apply(const double &x,const T &t, T &ret) * { * ret = "hallo" + t; * } * }; * void useForLoop() * { * std::string world; * ForLoop<Operation,1,10>::apply(1.,"hallo",world); * } * }; */ template< template< int > class Operation, int first, int last > struct ForLoop { static void apply () { Operation< first >::apply(); ForLoop< Operation, first+1, last >::apply(); } template< class T1 > static void apply ( T1 &p1 ) { Operation< first >::apply( p1 ); ForLoop< Operation, first+1, last >::apply( p1 ); } template< class T1, class T2 > static void apply ( T1 &p1, T2 &p2 ) { Operation< first >::apply( p1, p2 ); ForLoop< Operation, first+1, last >::apply( p1, p2 ); } template< class T1, class T2, class T3 > static void apply ( T1 &p1, T2 &p2, T3 &p3 ) { Operation< first >::apply( p1, p2, p3 ); ForLoop< Operation, first+1, last >::apply( p1, p2, p3 ); } template< class T1, class T2, class T3, class T4 > static void apply ( T1 &p1, T2 &p2, T3 &p3, T4 &p4 ) { Operation< first >::apply( p1, p2, p3, p4 ); ForLoop< Operation, first+1, last >::apply( p1, p2, p3, p4 ); } template< class T1, class T2, class T3, class T4, class T5 > static void apply ( T1 &p1, T2 &p2, T3 &p3, T4 &p4, T5 &p5 ) { Operation< first >::apply( p1, p2, p3, p4, p5 ); ForLoop< Operation, first+1, last >::apply( p1, p2, p3, p4, p5 ); } private: dune_static_assert( (first <= last), "ForLoop: first > last" ); }; template< template< int > class Operation, int last > struct ForLoop< Operation, last, last > { static void apply () { Operation< last >::apply(); } template< class T1 > static void apply ( T1 &p1 ) { Operation< last >::apply( p1 ); } template< class T1, class T2 > static void apply ( T1 &p1, T2 &p2 ) { Operation< last >::apply( p1, p2 ); } template< class T1, class T2, class T3 > static void apply ( T1 &p1, T2 &p2, T3 &p3 ) { Operation< last >::apply( p1, p2, p3 ); } template< class T1, class T2, class T3, class T4 > static void apply ( T1 &p1, T2 &p2, T3 &p3, T4 &p4 ) { Operation< last >::apply( p1, p2, p3, p4 ); } template< class T1, class T2, class T3, class T4, class T5 > static void apply ( T1 &p1, T2 &p2, T3 &p3, T4 &p4, T5 &p5 ) { Operation< last >::apply( p1, p2, p3, p4, p5 ); } }; } #endif