Variant event types

Description

Event types representing a type-safe union of event types.

Variant events can be used to treat a number of event types as a single type, for example to allow buffering of a stream of more than one type of event.

The type tcspc::variant_event is a thin wrapper around std::variant. In generic code working with an unknown set of event types, the type alias tcspc::variant_or_single_event is useful to avoid the overhead of std::variant when there is only one event type.

An equivalent to std::visit for use with tcspc::variant_or_single_event is provided: tcspc::visit_variant_or_single_event().

Topics
	Visiting a variant-or-single event
	Equivalent of std::visit for tcspc::variant_or_single_event.

Classes
class	tcspc::variant_event< EventList >
	Variant event. More...

Typedefs
template<typename EventList>
using	tcspc::variant_or_single_event
	Select the plain event if single, otherwise tcspc::variant_event.

Typedef Documentation

variant_or_single_event

template<typename EventList>

using tcspc::variant_or_single_event

Initial value:

 
typename internal::variant_or_single_event_impl<
    unique_type_list_t<EventList>>::type

Select the plain event if single, otherwise tcspc::variant_event.

When EventList contains a single event type, resolves to that event. Otherwise resolves to tcspc::variant_event<EventList>.

See also

Visiting a variant-or-single event