Tuple Utilities

Utility classes which can be used with std::tuple. More...

Files
file	tupleutility.hh
	Contains utility classes which can be used with std::tuple.

Classes
struct	Dune::NullPointerInitialiser< T >
	A helper template that initializes a std::tuple consisting of pointers to nullptr. More...
struct	Dune::ForEachType< TE, T >
	Helper template to clone the type definition of a std::tuple with the storage types replaced by a user-defined rule. More...
class	Dune::TransformTupleFunctor< TE, Args >
struct	Dune::AddRefTypeEvaluator< T >
	TypeEvaluator to turn a type T into a reference to T More...
struct	Dune::AddPtrTypeEvaluator< T >
	TypeEvaluator to turn a type T into a pointer to T More...
struct	Dune::AtType< N, Tuple >
	Type for reverse element access. More...
struct	Dune::At< N >
	Reverse element access. More...
struct	Dune::PointerPairDeletor< Tuple >
	Deletes all objects pointed to in a std::tuple of pointers. More...
class	Dune::FirstPredicateIndex< Tuple, Predicate, start, size >
	Finding the index of a certain type in a std::tuple. More...
struct	Dune::IsType< T >
	Generator for predicates accepting one particular type. More...
struct	Dune::IsType< T >::Predicate< U >
	The actual predicate. More...
struct	Dune::FirstTypeIndex< Tuple, T, start >
	Find the first occurrence of a type in a std::tuple. More...
struct	Dune::PushBackTuple< Tuple, T >
	Helper template to append a type to a std::tuple. More...
struct	Dune::PushFrontTuple< Tuple, T >
	Helper template to prepend a type to a std::tuple. More...
struct	Dune::ReduceTuple< F, Tuple, Seed, N >
	Apply reduce with meta binary function to template. More...
struct	Dune::ReduceTuple< F, Tuple, Seed, 0 >
	Apply reduce with meta binary function to template. More...
struct	Dune::JoinTuples< Head, Tail >
	Join two std::tuple's. More...
struct	Dune::FlattenTuple< Tuple >
	Flatten a std::tuple of std::tuple's. More...

Typedefs
typedef F< Accumulated, Value >::type	Dune::ReduceTuple< F, Tuple, Seed, N >::type
	Result of the reduce operation.
typedef Seed	Dune::ReduceTuple< F, Tuple, Seed, 0 >::type
	Result of the reduce operation.
typedef ReduceTuple< PushBackTuple, Tail, Head >::type	Dune::JoinTuples< Head, Tail >::type
	Result of the join operation.
typedef ReduceTuple< JoinTuples, Tuple >::type	Dune::FlattenTuple< Tuple >::type
	Result of the flatten operation.

Functions
template<class Tuple , class Functor >
auto	Dune::genericTransformTuple (Tuple &&t, Functor &&f) -> decltype(genericTransformTupleBackend(t, f))
template<template< class > class TypeEvaluator, class Tuple , class... Args>
auto	Dune::transformTuple (Tuple &&orig, Args &&... args) -> decltype(genericTransformTuple(orig, makeTransformTupleFunctor< TypeEvaluator >(args...)))

Detailed Description

Utility classes which can be used with std::tuple.

Function Documentation

genericTransformTuple()

template<class Tuple , class Functor >

auto Dune::genericTransformTuple	(	Tuple &&	t,
		Functor &&	f
	)		-> decltype(genericTransformTupleBackend(t, f))

This function does for the value of a std::tuple what ForEachType does for the type of a std::tuple: it transforms the value using a user-provided policy functor.

Parameters

t	The std::tuple value to transform.
f	The functor to use to transform the values.

The functor should have the following form:

struct Functor
{
  template<class>
  struct TypeEvaluator
  {
    typedef user-defined Type;
  };
 
  template<class T>
  typename TypeEvaluator<T>::Type operator()(T& val);
 
  template<class T>
  typename TypeEvaluator<T>::Type operator()(T& val) const;
 
  template<class T>
  typename TypeEvaluator<T>::Type operator()(const T& val);
 
  template<class T>
  typename TypeEvaluator<T>::Type operator()(const T& val) const;
};

The member class template TypeEvaluator should be a class template suitable as the TypeEvaluator template parameter for ForEachType. The function call operator operator() is used to transform the value; only the signatures of operator() which are actually used must be present.

Referenced by Dune::transformTuple().

transformTuple()

template<template< class > class TypeEvaluator, class Tuple , class... Args>

auto Dune::transformTuple	(	Tuple &&	orig,
		Args &&...	args
	)		-> decltype(genericTransformTuple(orig, makeTransformTupleFunctor<TypeEvaluator>(args...)))

This function provides functionality similar to genericTransformTuple(), although less general and closer in spirit to ForEachType.

Template Parameters

TypeEvaluator	Used as the TE template argument to TransformTupleFunctor internally.
Tuple	Type of the std::tuple to transform.
Args	Types of extra argument to call the transformation function with.

Parameters

orig	Tuple value to be transformed.
args	Extra arguments values to provide to the transformation function.

The TypeEvaluator class template should be suitable as the TE template argument for TransformTupleFunctor. It has the following form (an extension of the TypeEvaluator template argument of ForEachType):

template <class T>
struct TypeEvaluator
{
  typedef UserDefined Type;
 
  template<class... Args>
  static Type apply(T& t, Args&... args);
};

See also

genericTransforTuple(), ForEachType, AddRefTypeEvaluator, and AddPtrTypeEvaluator.

References Dune::genericTransformTuple().