Core processors

Description

Basic and generic processors.

Topics
	Filtering processors
	Processors for filtering events.
	Batching and unbatching processors
	Processors that aggregate events into batches or extract individual events from batches.
	Multiplexing and demultiplexing processors
	Processors that combine events of different types into a variant type and back.
	Stopping processors
	Processors that stop processing when a given event is received.

Classes
class	tcspc::null_sink
	Processor that sinks any event and the end-of-stream and does nothing. More...
class	tcspc::type_erased_processor< EventList >
	Processor that type-erases the downstream processor. More...

Functions
template<typename Event, typename Downstream>
auto	tcspc::append (Event event, Downstream downstream)
	Create a processor that inserts an event at the end of the stream.
template<typename Downstream>
auto	tcspc::null_source (Downstream downstream)
	Create a processor that sources an empty stream.
template<typename Event, typename Downstream>
auto	tcspc::prepend (Event event, Downstream downstream)
	Create a processor that inserts an event at the beginning of the stream.

Function Documentation

append()

template<typename Event, typename Downstream>

auto tcspc::append	(	Event	event,
		Downstream	downstream )

Create a processor that inserts an event at the end of the stream.

All events are passed through. Before flushing, the given event is emitted.

Note

event is only appended upon a flush; if processing is ended by tcspc::end_of_processing being thrown by a downstream processor, this processor has no effect.

Template Parameters

Event	type of event to append (usually deduced)
Downstream	downstream processor type (usually deduced)

Parameters

event	event to append
downstream	downstream processor

Returns

processor

Events handled

• Any type: pass through with no action
• Flush: emit event; pass through

null_source()

template<typename Downstream>

auto tcspc::null_source

(

Downstream

downstream

)

Create a processor that sources an empty stream.

Template Parameters

Downstream

downstream processor type

Parameters

downstream

downstream processor

Returns

processor

Events handled

• Flush: pass through with no action

prepend()

template<typename Event, typename Downstream>

auto tcspc::prepend	(	Event	event,
		Downstream	downstream )

Create a processor that inserts an event at the beginning of the stream.

All events are passed through. Before the first event is passed through, the given event is emitted.

Template Parameters

Event	type of event to prepend (usually deduced)
Downstream	downstream processor type (usually deduced)

Parameters

event	event to prepend
downstream	downstream processor

Returns

processor

Events handled

• Any type: if the first event ever, emit event; pass through
• Flush: pass through with no action