clanguml::common::optional_ref< T > Class Template Reference

Simple optional reference type. More...

Detailed Description

template<typename T>
class clanguml::common::optional_ref< T >

Simple optional reference type.

This class template provides a convenient way around the std::optional limitation of not allowing references. This is useful for storing references to diagram elements in various views, and writing methods which return can return an empty value if the diagram does not contain something.

This is not an owning type - it will not accept an rvalue - the actual value must be stored somewhere else as lvalue or some kind of smart pointer.

Note

Probably unsafe - do not use at home.

Template Parameters

T	Type of reference

Definition at line 117 of file types.h.

#include <types.h>

Public Types
using	optional_type = T

Public Member Functions
	optional_ref ()=default
	optional_ref (T *value)
	optional_ref (const T *value)
	optional_ref (T &value)
	optional_ref (const T &value)
	optional_ref (optional_ref &right)
template<typename V , typename = std::enable_if< std::is_base_of_v<optional_type, typename V::optional_type> || std::is_same_v<optional_type, typename V::optional_type>>>
	optional_ref (const V &t)
template<typename V , typename = std::enable_if< std::is_base_of_v<optional_type, typename V::optional_type> || std::is_same_v<optional_type, typename V::optional_type>>>
	optional_ref (V &&t)
template<typename V , typename = std::enable_if<std::is_base_of_v<optional_type, V>>>
	optional_ref (const std::reference_wrapper< V > &t)
optional_ref &	operator= (const optional_ref &right)
optional_ref &	operator= (optional_ref &&right) noexcept
bool	has_value () const noexcept
	operator bool () const noexcept
const T &	value () const
T &	value ()
T &	operator* ()
const T &	operator* () const
void	reset ()
T *	get () const

Private Attributes
T *	value_ {nullptr}

Member Typedef Documentation

optional_type

template<typename T >

using clanguml::common::optional_ref< T >::optional_type = T

Definition at line 119 of file types.h.

Constructor & Destructor Documentation

optional_ref() [1/9]

template<typename T >

clanguml::common::optional_ref< T >::optional_ref ( )

default

optional_ref() [2/9]

template<typename T >

clanguml::common::optional_ref< T >::optional_ref ( T *  value )

inline

Definition at line 123 of file types.h.

        : value_{value}
    {
    }

optional_ref() [3/9]

template<typename T >

clanguml::common::optional_ref< T >::optional_ref ( const T *  value )

inline

Definition at line 128 of file types.h.

        : value_{value}
    {
    }

optional_ref() [4/9]

template<typename T >

clanguml::common::optional_ref< T >::optional_ref ( T &  value )

inline

Definition at line 133 of file types.h.

        : value_{&value}
    {
    }

optional_ref() [5/9]

template<typename T >

clanguml::common::optional_ref< T >::optional_ref ( const T &  value )

inline

Definition at line 138 of file types.h.

        : value_{&value}
    {
    }

optional_ref() [6/9]

template<typename T >

clanguml::common::optional_ref< T >::optional_ref ( optional_ref< T > &  right )

inline

Definition at line 143 of file types.h.

        : value_{right.get()}
    {
    }

optional_ref() [7/9]

template<typename T >

template<typename V , typename = std::enable_if< std::is_base_of_v<optional_type, typename V::optional_type> || std::is_same_v<optional_type, typename V::optional_type>>>

clanguml::common::optional_ref< T >::optional_ref ( const V &  t )

inline

Definition at line 152 of file types.h.

        : value_{t.get()}
    {
    }

optional_ref() [8/9]

template<typename T >

template<typename V , typename = std::enable_if< std::is_base_of_v<optional_type, typename V::optional_type> || std::is_same_v<optional_type, typename V::optional_type>>>

clanguml::common::optional_ref< T >::optional_ref ( V &&  t )

inline

Definition at line 161 of file types.h.

        : value_{t.get()}
    {
        t.reset();
    }

optional_ref() [9/9]

template<typename T >

template<typename V , typename = std::enable_if<std::is_base_of_v<optional_type, V>>>

clanguml::common::optional_ref< T >::optional_ref ( const std::reference_wrapper< V > &  t )

inline

Definition at line 169 of file types.h.

        : value_{&t.get()}
    {
    }

Member Function Documentation

get()

template<typename T >

T * clanguml::common::optional_ref< T >::get ( ) const

inline

Definition at line 223 of file types.h.

{ return value_; }

has_value()

template<typename T >

bool clanguml::common::optional_ref< T >::has_value ( ) const

inlinenoexcept

Definition at line 193 of file types.h.

{ return value_ != nullptr; }

operator bool()

template<typename T >

clanguml::common::optional_ref< T >::operator bool ( ) const

inlinenoexcept

Definition at line 195 of file types.h.

{ return has_value(); }

operator*() [1/2]

template<typename T >

T & clanguml::common::optional_ref< T >::operator* ( )

inline

Definition at line 209 of file types.h.

    {
        assert(value_ != nullptr);
        return *value_;
    }

operator*() [2/2]

template<typename T >

const T & clanguml::common::optional_ref< T >::operator* ( ) const

inline

Definition at line 215 of file types.h.

    {
        assert(value_ != nullptr);
        return *value_;
    }

operator=() [1/2]

template<typename T >

optional_ref & clanguml::common::optional_ref< T >::operator= ( const optional_ref< T > &  right )

inline

Definition at line 174 of file types.h.

    {
        if (this == &right)
            return *this;
 
        value_ = right.value_;
        return *this;
    }

operator=() [2/2]

template<typename T >

optional_ref & clanguml::common::optional_ref< T >::operator= ( optional_ref< T > &&  right )

inlinenoexcept

Definition at line 183 of file types.h.

    {
        if (this == &right)
            return *this;
 
        value_ = right.value_;
        right.reset();
        return *this;
    }

reset()

template<typename T >

void clanguml::common::optional_ref< T >::reset ( )

inline

Definition at line 221 of file types.h.

{ value_ = nullptr; }

value() [1/2]

template<typename T >

T & clanguml::common::optional_ref< T >::value ( )

inline

Definition at line 203 of file types.h.

    {
        assert(value_ != nullptr);
        return *value_;
    }

value() [2/2]

template<typename T >

const T & clanguml::common::optional_ref< T >::value ( ) const

inline

Definition at line 197 of file types.h.

    {
        assert(value_ != nullptr);
        return *value_;
    }

Member Data Documentation

value_

template<typename T >

T* clanguml::common::optional_ref< T >::value_ {nullptr}

private

Definition at line 226 of file types.h.

---

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

• src/common/types.h