DGtal::functors::PointFunctorHolder< TPoint, TValue, TFunctor > Class Template Reference

Aim: hold any object callable on points as a DGtal::concepts::CPointFunctor model. More...

#include <DGtal/kernel/PointFunctorHolder.h>

Public Types
using	Self = PointFunctorHolder<TPoint, TValue, TFunctor>
using	Point = TPoint
using	Value = TValue
using	Functor = TFunctor

Public Member Functions
template<typename Function, typename std::enable_if<!std::is_base_of< PointFunctorHolder, typename std::decay< Function >::type >::value, int >::type = 0>
	PointFunctorHolder (Function &&fn)
	Constructor.
Value	operator() (Point const &aPoint) const
	Evaluates the functor at the given point.
void	selfDisplay (std::ostream &out) const
	Writes/Displays the object on an output stream.
constexpr bool	isValid () const
	Checks the validity/consistency of the object.

Private Attributes
Functor	myFunctor
	The held functor.

Detailed Description

template<typename TPoint, typename TValue, typename TFunctor>
class DGtal::functors::PointFunctorHolder< TPoint, TValue, TFunctor >

Aim: hold any object callable on points as a DGtal::concepts::CPointFunctor model.

Template Parameters

TPoint	Point type.
TValue	Value type returned by the functor.
TFunctor	Type of the functor.

The functor must accept a point and return a value whose type is Value.

Warning

This class is not meant to be directly constructed by the user. Use instead the holdPointFunctor helper that will choose the more appropriate storage type for the functor depending on the given callable object.

A typical usage would be:

using Point = PointVector<2, int>;
auto fn = holdPointFunctor<Point>( // auto-deduced Value template
  [] (Point const& pt) { return pt.norm(); }
);

In you want to use a function instead of a functor or lambda, consider wrapping it into a lambda to avoid a performance penalty due to the fact that a pointer to a function cannot be inlined:

using Point = PointVector<2, int>;
auto fn = holdPointFunctor<Point>( // auto-deduced Value template
  [] (Point const& pt) { return my_function(pt); }
);

You can find more informations about how to use this class appropriately in the module about Using functions, functors and lambdas in DGtal.

See also

holdPointFunctor, FunctorHolder, Using functions, functors and lambdas in DGtal

Definition at line 95 of file PointFunctorHolder.h.

Member Typedef Documentation

Functor

template<typename TPoint, typename TValue, typename TFunctor>

using DGtal::functors::PointFunctorHolder< TPoint, TValue, TFunctor >::Functor = TFunctor

Definition at line 104 of file PointFunctorHolder.h.

Point

template<typename TPoint, typename TValue, typename TFunctor>

using DGtal::functors::PointFunctorHolder< TPoint, TValue, TFunctor >::Point = TPoint

Definition at line 102 of file PointFunctorHolder.h.

Self

template<typename TPoint, typename TValue, typename TFunctor>

using DGtal::functors::PointFunctorHolder< TPoint, TValue, TFunctor >::Self = PointFunctorHolder<TPoint, TValue, TFunctor>

Definition at line 101 of file PointFunctorHolder.h.

Value

template<typename TPoint, typename TValue, typename TFunctor>

using DGtal::functors::PointFunctorHolder< TPoint, TValue, TFunctor >::Value = TValue

Definition at line 103 of file PointFunctorHolder.h.

Constructor & Destructor Documentation

PointFunctorHolder()

template<typename TPoint, typename TValue, typename TFunctor>

template<typename Function, typename std::enable_if<!std::is_base_of< PointFunctorHolder, typename std::decay< Function >::type >::value, int >::type = 0>

DGtal::functors::PointFunctorHolder< TPoint, TValue, TFunctor >::PointFunctorHolder ( Function && fn )

inlineexplicit

Constructor.

Template Parameters

Function

The type of the callable object (auto-deduced).

Parameters

fn	The callable object.

Definition at line 119 of file PointFunctorHolder.h.

      : myFunctor(std::forward<Function>(fn))
  {
  }

References myFunctor.

Member Function Documentation

isValid()

template<typename TPoint, typename TValue, typename TFunctor>

bool DGtal::functors::PointFunctorHolder< TPoint, TValue, TFunctor >::isValid ( ) const

inlineconstexpr

Checks the validity/consistency of the object.

Returns

'true' if the object is valid, 'false' otherwise.

Definition at line 152 of file PointFunctorHolder.h.

    {
      return true;
    }

operator()()

template<typename TPoint, typename TValue, typename TFunctor>

Value DGtal::functors::PointFunctorHolder< TPoint, TValue, TFunctor >::operator() ( Point const & aPoint ) const

inline

Evaluates the functor at the given point.

Parameters

aPoint

The point.

Definition at line 132 of file PointFunctorHolder.h.

    {
      return myFunctor( aPoint );
    }

References aPoint, and myFunctor.

selfDisplay()

template<typename TPoint, typename TValue, typename TFunctor>

void DGtal::functors::PointFunctorHolder< TPoint, TValue, TFunctor >::selfDisplay ( std::ostream & out ) const

inline

Writes/Displays the object on an output stream.

Parameters

out	the output stream where the object is written.

Definition at line 142 of file PointFunctorHolder.h.

    {
      out << "[PointFunctorHolder] holding a " << myFunctor;
    }

References myFunctor.

Field Documentation

myFunctor

template<typename TPoint, typename TValue, typename TFunctor>

Functor DGtal::functors::PointFunctorHolder< TPoint, TValue, TFunctor >::myFunctor

private

The held functor.

Definition at line 160 of file PointFunctorHolder.h.

Referenced by operator()(), PointFunctorHolder(), and selfDisplay().

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The documentation for this class was generated from the following file:

• PointFunctorHolder.h