morph::reactive::Subscription< R > Class Template Reference

The latest R the bridge published on a handler's instance, as reactive state. More...

#include <control.hpp>

Public Member Functions
template<typename M, typename S>
	Subscription (Runtime &runtime, bridge::BridgeHandler< M, S > &handler)
	Subscribes to every R published on handler's instance, and checks the handler's callback executor against the runtime's owner (detail::checkHandlerExecutor).
	Subscription (Subscription const &)=delete
Subscription &	operator= (Subscription const &)=delete
	Subscription (Subscription &&)=delete
Subscription &	operator= (Subscription &&)=delete
std::optional< R > const &	latest () const
	The latest published value. Tracked.

Detailed Description

template<typename R>
class morph::reactive::Subscription< R >

The latest R the bridge published on a handler's instance, as reactive state.

Uses the handler's one subscription slot for R: two consumers of the same R use two handlers. The subscription is gated by a scope the Subscription owns, so a publish delivered after it is destroyed — one already queued included — is dropped. The handler keeps the dead entry until it is destroyed or subscribes to R again. A delivery off the Runtime's owner is reported (detail::site::kOffOwner) and dropped.

latest() is state, not an event stream: when R compares with ==, a publish equal to the current value does not notify. For something to happen on every publish, use Query::refreshOn.

Template Parameters

R	The published result type.

Definition at line 704 of file control.hpp.

Constructor & Destructor Documentation

Subscription()

template<typename R>

template<typename M, typename S>

morph::reactive::Subscription< R >::Subscription ( Runtime & runtime, bridge::BridgeHandler< M, S > & handler )

inline

Subscribes to every R published on handler's instance, and checks the handler's callback executor against the runtime's owner (detail::checkHandlerExecutor).

Template Parameters

M	The handler's model type.
S	The handler's sharing policy.

Parameters

runtime	The runtime. Borrowed: it must outlive the subscription.
handler	The handler whose instance publishes; its GUI executor must be the runtime's owner. Borrowed: it must outlive the subscription.

Definition at line 714 of file control.hpp.

Member Function Documentation

latest()

template<typename R>

std::optional< R > const & morph::reactive::Subscription< R >::latest ( ) const

inlinenodiscard

The latest published value. Tracked.

Returns

The value, or nullopt before the first publish. Valid until the next publish.

Definition at line 733 of file control.hpp.

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

• morph/reactive/control.hpp