Aleph::CA::Composite_Observer< Observers > Class Template Reference

Variadic adaptor that fan-outs notifications to many observers. More...

#include <ca-observer.H>

Public Member Functions
	Composite_Observer (Observers... observers)
	Build the composite from child observers.
template<std::size_t I>
const auto &	get () const noexcept
	Return read-only access to a child observer.
template<std::size_t I>
auto &	get () noexcept
	Return mutable access to a child observer.
template<typename Lattice >
void	on_step_begin (std::size_t step, const Lattice &frame)
	Forward a step-begin event to every child observer.
template<typename Lattice >
void	on_step_end (std::size_t step, const Lattice &frame)
	Forward a step-end event to every child observer.

Static Public Member Functions
static constexpr std::size_t	size () noexcept
	Return the number of child observers.

Private Attributes
std::tuple< Observers... >	obs_

Detailed Description

template<typename... Observers>
class Aleph::CA::Composite_Observer< Observers >

Variadic adaptor that fan-outs notifications to many observers.

Composite_Observer<O1, O2, ...> owns its child observers by value (move-constructed at build time) and forwards on_step_begin / on_step_end to each one in declaration order. This lets the engine's single pre/post hook host an arbitrary number of independent observers.

Template Parameters

Observers

types of the child observers.

Definition at line 128 of file ca-observer.H.

Constructor & Destructor Documentation

Composite_Observer()

template<typename... Observers>

Aleph::CA::Composite_Observer< Observers >::Composite_Observer ( Observers...  observers )

inlineexplicit

Build the composite from child observers.

Reference types in Observers... are preserved and borrowed; value types are moved into the tuple and owned by the composite.

Parameters

[in]

observers

child observers to store or reference.

Exceptions

Any	exception thrown while constructing the internal tuple.

Complexity

O(number of observers) time and space.

Thread-safety

Not thread-safe for concurrent callback writes. Concurrent readers are safe only if the referenced/owned observers are safe.

Definition at line 148 of file ca-observer.H.

Member Function Documentation

get() [1/2]

template<typename... Observers>

template<std::size_t I>

const auto & Aleph::CA::Composite_Observer< Observers >::get ( ) const

inlinenoexcept

Return read-only access to a child observer.

Template Parameters

I	child index.

Returns

const reference to the selected observer.

Exceptions

This	function does not throw.

Definition at line 157 of file ca-observer.H.

References Aleph::CA::Composite_Observer< Observers >::obs_.

get() [2/2]

template<typename... Observers>

template<std::size_t I>

auto & Aleph::CA::Composite_Observer< Observers >::get ( )

inlinenoexcept

Return mutable access to a child observer.

Template Parameters

I	child index.

Returns

mutable reference to the selected observer.

Exceptions

This	function does not throw.

Definition at line 168 of file ca-observer.H.

References Aleph::CA::Composite_Observer< Observers >::obs_.

on_step_begin()

template<typename... Observers>

template<typename Lattice >

void Aleph::CA::Composite_Observer< Observers >::on_step_begin ( std::size_t  step, const Lattice &  frame  )

inline

Forward a step-begin event to every child observer.

Template Parameters

Lattice

lattice type.

Parameters

[in]	step	step index about to run.
[in]	frame	current frame before the step.

Exceptions

Any	exception thrown by a child observer.

Complexity

O(number of observers).

Definition at line 192 of file ca-observer.H.

References Aleph::blossom_maximum_cardinality_matching(), and Aleph::CA::Composite_Observer< Observers >::obs_.

on_step_end()

template<typename... Observers>

template<typename Lattice >

void Aleph::CA::Composite_Observer< Observers >::on_step_end ( std::size_t  step, const Lattice &  frame  )

inline

Forward a step-end event to every child observer.

Template Parameters

Lattice

lattice type.

Parameters

[in]	step	step index just completed.
[in]	frame	current frame after the step.

Exceptions

Any	exception thrown by a child observer.

Complexity

O(number of observers).

Definition at line 210 of file ca-observer.H.

References Aleph::blossom_maximum_cardinality_matching(), and Aleph::CA::Composite_Observer< Observers >::obs_.

size()

template<typename... Observers>

static constexpr std::size_t Aleph::CA::Composite_Observer< Observers >::size ( )

inlinestaticconstexprnoexcept

Return the number of child observers.

Returns

sizeof...(Observers).

Exceptions

This	function does not throw.

Definition at line 177 of file ca-observer.H.

Member Data Documentation

obs_

template<typename... Observers>

std::tuple<Observers...> Aleph::CA::Composite_Observer< Observers >::obs_

private

Definition at line 130 of file ca-observer.H.

Referenced by Aleph::CA::Composite_Observer< Observers >::get(), Aleph::CA::Composite_Observer< Observers >::get(), Aleph::CA::Composite_Observer< Observers >::on_step_begin(), and Aleph::CA::Composite_Observer< Observers >::on_step_end().

---

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

• ca-observer.H