P4::Util::Enumerator< T > Class Template Reference

Type-erased Enumerator interface. More...

#include <enumerator.h>

Inheritance diagram for P4::Util::Enumerator< T >:

Public Types
using	value_type = T

Public Member Functions
bool	any ()
	True if the enumerator has at least one element.
template<typename S >
Enumerator< S > *	as ()
	Cast to an enumerator of S objects.
EnumeratorHandle< T >	begin ()
virtual Enumerator< T > *	concat (Enumerator< T > *other)
	Append all elements of other after all elements of this.
uint64_t	count ()
	Enumerate all elements and return the count.
EnumeratorHandle< T >	end ()
virtual T	getCurrent () const =0
	Get current element in the collection.
template<typename Mapper >
Enumerator< std::invoke_result_t< Mapper, T > > *	map (Mapper map)
	Apply specified function to all elements of this enumerator.
virtual bool	moveNext ()=0
T	next ()
	Next element; throws if there are no elements.
T	nextOrDefault ()
	Next element, or the default value if none exists.
virtual void	reset ()
	Move back to the beginning of the collection.
T	single ()
	The only next element; throws if the enumerator does not have exactly 1 element.
T	singleOrDefault ()
const char *	stateName () const
std::vector< T >	toVector ()
template<typename Filter >
Enumerator< T > *	where (Filter filter)
	Return an enumerator returning all elements that pass the filter.

Static Public Member Functions
static Enumerator< T > *	concatAll (Enumerator< Enumerator< T > * > *inputs)
	Concatenate all these collections into a single one.
template<typename Container >
static Enumerator< typename Container::value_type > *	createEnumerator (const Container &data)
template<typename Iter >
static Enumerator< typename Iter::value_type > *	createEnumerator (Iter begin, Iter end)
template<typename Iter >
static Enumerator< typename Iter::value_type > *	createEnumerator (iterator_range< Iter > range)
static Enumerator< T > *	emptyEnumerator ()

Protected Attributes
EnumeratorState	state = EnumeratorState::NotStarted

Static Protected Attributes
static std::vector< T >	emptyVector

Friends
template<typename S >
class	EnumeratorHandle

Detailed Description

template<class T>
class P4::Util::Enumerator< T >

Type-erased Enumerator interface.

Member Function Documentation

concat()

template<typename T >

Enumerator< T > * P4::Util::Enumerator< T >::concat ( Enumerator< T > * other )

virtual

Append all elements of other after all elements of this.

Reimplemented in P4::Util::ConcatEnumerator< T >.

getCurrent()

template<class T >

virtual T P4::Util::Enumerator< T >::getCurrent ( ) const

pure virtual

Get current element in the collection.

Implemented in P4::Util::AsEnumerator< T, S >, P4::Util::ConcatEnumerator< T >, P4::Util::EmptyEnumerator< T >, P4::Util::FilterEnumerator< T, Filter >, P4::Util::IteratorEnumerator< Iter >, P4::Util::MapEnumerator< T, S, Mapper >, and P4::Util::SingleEnumerator< T >.

moveNext()

template<class T >

virtual bool P4::Util::Enumerator< T >::moveNext ( )

pure virtual

Move to next element in the collection; return false if the next element does not exist

Implemented in P4::Util::AsEnumerator< T, S >, P4::Util::ConcatEnumerator< T >, P4::Util::EmptyEnumerator< T >, P4::Util::FilterEnumerator< T, Filter >, P4::Util::IteratorEnumerator< Iter >, P4::Util::MapEnumerator< T, S, Mapper >, and P4::Util::SingleEnumerator< T >.

reset()

template<class T >

virtual void P4::Util::Enumerator< T >::reset ( )

inlinevirtual

Move back to the beginning of the collection.

Reimplemented in P4::Util::AsEnumerator< T, S >, P4::Util::ConcatEnumerator< T >, P4::Util::FilterEnumerator< T, Filter >, and P4::Util::MapEnumerator< T, S, Mapper >.

singleOrDefault()

template<class T >

T P4::Util::Enumerator< T >::singleOrDefault ( )

inline

The only next element or default value if none exists; throws if the enumerator does not have exactly 0 or 1 element