ultra::alps_layer_pair< Layer > Class Template Reference

#include <alps.h>

Public Member Functions
	alps_layer_pair (Layer &l) noexcept
	alps_layer_pair (Layer &p, Layer &s) noexcept
constexpr std::size_t	size () const noexcept
constexpr bool	has_secondary () const noexcept
constexpr auto	begin () const noexcept
constexpr auto	end () const noexcept
constexpr Layer &	primary () const noexcept
constexpr Layer &	secondary () const noexcept
Layer &	random (double p_pri) const

Detailed Description

template<class Layer>
class ultra::alps_layer_pair< Layer >

Lightweight view over one or two ALPS layers.

Template Parameters

Layer

layer type. Can be const to model read-only access.

This class stores references to a primary layer and, optionally, a secondary layer. It's designed to avoid dynamic allocation in helper functions that, by policy, return either one or two eligible layers.

The object is iterable. When no secondary layer is present, size() is 1 and the iteration covers only the primary layer.

Warning

alps_layer_pair does not own the layers. The referenced layers must outlive the alps_layer_pair instance.

Note

When constructed with a single layer, the internal storage keeps two copies of the primary reference, but size()/iteration expose only one element.

Constructor & Destructor Documentation

alps_layer_pair() [1/2]

template<class Layer>

ultra::alps_layer_pair< Layer >::alps_layer_pair ( Layer & l )

inlinenoexcept

Builds a pair with a single eligible layer (primary only).

Parameters

[in]

l

primary layer

After construction size() == 1 and has_secondary() == false.

alps_layer_pair() [2/2]

template<class Layer>

ultra::alps_layer_pair< Layer >::alps_layer_pair ( Layer & p, Layer & s )

inlinenoexcept

Builds a pair with two eligible layers (primary and secondary).

Parameters

[in]	p	primary layer
[in]	s	secondary layer

After construction size() == 2 and has_secondary() == true.

Member Function Documentation

begin()

template<class Layer>

auto ultra::alps_layer_pair< Layer >::begin ( ) const

inlinenodiscardconstexprnoexcept

Returns

iterator to the first exposed layer reference

end()

template<class Layer>

auto ultra::alps_layer_pair< Layer >::end ( ) const

inlinenodiscardconstexprnoexcept

Returns

iterator one past the last exposed layer reference

has_secondary()

template<class Layer>

bool ultra::alps_layer_pair< Layer >::has_secondary ( ) const

inlinenodiscardconstexprnoexcept

Returns

true if a secondary layer is present

primary()

template<class Layer>

Layer & ultra::alps_layer_pair< Layer >::primary ( ) const

inlinenodiscardconstexprnoexcept

Returns

the primary layer

random()

template<class Layer>

Layer & ultra::alps_layer_pair< Layer >::random ( double p_pri ) const

inlinenodiscard

Picks a layer at random.

Parameters

[in]

p_pri

probability of selecting the primary layer

Returns

either primary() (with probability p_pri) or secondary() (with probability 1 - p_pri)

Precondition

0.0 < p_pri && p_pri <= 1.0.

Note

If no secondary layer is present, this function always returns primary(), regardless of p_pri.

secondary()

template<class Layer>

Layer & ultra::alps_layer_pair< Layer >::secondary ( ) const

inlinenodiscardconstexprnoexcept

Returns

the secondary layer

Precondition

has_secondary() == true

size()

template<class Layer>

std::size_t ultra::alps_layer_pair< Layer >::size ( ) const

inlinenodiscardconstexprnoexcept

Returns

number of exposed layers (1 or 2)

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

• alps.h