demotool/Sets.hh

/******************************************************************************/
/* SETS ***********************************************************************/
/******************************************************************************/

#ifndef _H_EBCL_SETS
#define _H_EBCL_SETS
#include <ebcl/Arrays.hh>
namespace ebcl {

// FIXME move this to utilities \/

// Define a structure that can be used as a tag
#define M_DEFINE_TAG( NAME ) \
	struct NAME { }
// Define a tag structure that can carry arguments
#define M_DEFINE_TEMPLATE_TAG( NAME , ARGS... ) \
	template< ARGS > \
	M_DEFINE_TAG( NAME )

// A structure that can be used to carry a tag structure instance
template< typename Tag >
struct UseTag
{
	const Tag tag;

	template< typename ... ArgTypes >
	constexpr UseTag( ArgTypes&&... args ) noexcept
		: tag( std::forward< ArgTypes >( args ) ... ) { }
};


// Implementation of a set of type Type. The actual implementation is
// determined by the ImplTag type.
template< typename Type , typename ImplTag >
	class T_SetImplementation;


// ArrayBacked implementation tag. InPlace is the amount of items to
// store in-place (0 will cause a T_Array to be used
M_DEFINE_TEMPLATE_TAG( ArrayBacked ,
	uint32_t InPlace ,
	uint32_t Growth = 0
);
//M_DEFINE_TAG( IndexBacked );


template< typename Type , uint32_t InPlace , uint32_t Growth >
class T_SetImplementation< Type , ArrayBacked< InPlace , Growth > >
{
    private:
	T_AutoArray< Type , InPlace ,
		Growth == 0 ? ( InPlace * 4 ) : Growth
	> data_;

    public:
	uint32_t size( ) const noexcept;
	int32_t indexOf( Type const& item ) const noexcept;

	bool add( Type const& item ) noexcept;
	bool add( Type&& item ) noexcept;
	bool remove( Type const& item ) noexcept;
};

template< typename Type , uint32_t Growth >
class T_SetImplementation< Type , ArrayBacked< 0 , Growth > >
{
    private:
	T_Array< Type > data_;

    public:
	template< uint32_t G = Growth , typename std::enable_if_t< G == 0 , int > = 0
	> T_SetImplementation( ) noexcept;
	template< uint32_t G = Growth , typename std::enable_if_t< G != 0 , int > = 0
	> T_SetImplementation( ) noexcept;

	uint32_t size( ) const noexcept;
	int32_t indexOf( Type const& item ) const noexcept;

	bool add( Type const& item ) noexcept;
	bool add( Type&& item ) noexcept;
	bool remove( Type const& item ) noexcept;
};

struct T_SetHelper
{
	using DefaultImplementation = ArrayBacked< 8 >; // FIXME should use Index by default

	template< typename Type
	> using DefaultType = T_SetImplementation<
			Type , DefaultImplementation >;

	template< typename Type
	> static constexpr auto DefaultSize{ sizeof( DefaultType< Type > ) };

	template< typename Type
	> static constexpr auto DefaultAlign{ alignof( DefaultType< Type > ) };

	enum E_Operation
	{
		INIT ,
		DESTROY ,

		SIZE ,
		INDEX_OF ,

		ADD_COPY ,
		ADD_MOVE ,
		REMOVE ,
	};

	template< typename Type , typename Impl
	> struct T_InPlaceHandler
	{
		static void shdl( E_Operation operation ,
				void* wArg ,
				void const* rArg ,
				void* output );
	};

	template< typename Type , typename Impl
	> struct T_HeapHandler
	{
		static void shdl( E_Operation operation ,
				void* wArg ,
				void const* rArg ,
				void* output );
	};

	template<
		typename Type , typename ImplTag ,
		typename Impl = T_SetImplementation< Type , ImplTag >
	> using T_Handler = std::conditional_t<
		sizeof( Impl ) <= DefaultSize< Type > ,
		T_InPlaceHandler< Type , ImplTag > ,
		T_HeapHandler< Type , ImplTag >
	>;

	using F_Handler = std::function<
		void( E_Operation , void* , void const* , void* ) >;
};

template< typename Type >
class T_Set
{
    private:

	std::aligned_storage_t<
		T_SetHelper::DefaultSize< Type > ,
		T_SetHelper::DefaultAlign< Type >
	> storage_;
	const T_SetHelper::F_Handler handler_;

    public:
	T_Set( ) noexcept;

	template< typename Tag
	> T_Set( UseTag< Tag > impl ) noexcept;

	~T_Set( );

	// ---------------------------------------------------------------------

	uint32_t size( ) const noexcept;
	bool contains( Type const& item ) const noexcept;
	int32_t indexOf( Type const& item ) const noexcept;

	// ---------------------------------------------------------------------

	bool add( Type const& item ) noexcept;
	bool add( Type&& item ) noexcept;
	bool remove( Type const& item ) noexcept;
};


}
#endif // _H_EBCL_SETS
// XXX #include <ebcl/inline/Sets.hh>
#include "Sets-inline.hh"