An RAII handle type which owns an opaque resource of a specified type, and calls a designated function to close the resource upon destruction. More...

#include <handle.hpp>

Public Member Functions
	handle () noexcept
	Constructs a handle which does not own a resource. More...

	handle (Resource resource) noexcept
	Constructs a handle which owns the specified resource. More...

	handle (const handle &)=delete

handle &	operator= (const handle &)=delete

	handle (handle &&other) noexcept
	Constructs a handle which takes ownership of a resource (if any) from another handle. More...

handle &	operator= (handle &&other) noexcept
	Releases the resource (if any) owned by this handle and takes ownership of a resource (if any) from another handle. More...

	~handle () noexcept
	Closes the resource (if any) owned by this handle. More...

Resource	get () noexcept
	Returns the resource (if any) owned by this handle. More...

const Resource	get () const noexcept
	Returns the resource (if any) owned by this handle. More...

	operator Resource () noexcept
	Returns the resource (if any) owned by this handle. More...

	operator const Resource () const noexcept
	Returns the resource (if any) owned by this handle. More...

	operator bool () const noexcept
	Tests whether this handle owns a resource. More...

void	close () noexcept
	Closes the resource (if any) owned by this handle by calling `CloseFunc`. More...

Resource	release () noexcept
	Releases (without closing) and returns the underlying resource. More...

Detailed Description

template<typename Resource, Resource Closed, auto CloseFunc, std::enable_if_t< std::is_nothrow_copy_constructible_v< Resource > &&std::is_nothrow_swappable_v< Resource > &&std::is_function_v< std::remove_pointer_t< decltype(CloseFunc)> > &&(std::is_invocable_v< decltype(CloseFunc), Resource >||std::is_invocable_v< decltype(CloseFunc)>)> * = nullptr>
class w::handle< Resource, Closed, CloseFunc, >

An RAII handle type which owns an opaque resource of a specified type, and calls a designated function to close the resource upon destruction.

The type is moveable but not copyable, and provides semantics similar to std::unique_ptr. Most members are noexcept for underlying resource types which are nothrow-swappable and nothrow-copy-constructible.

Template Parameters

Resource	The type of the resource to own. This type must be nothrow-comparable, nothrow-copy-constructible and nothrow-swappable.
Closed	A special value which indicates a closed resource.
CloseFunc	A function which closes a resource. The function must not throw exceptions, and preferably should be marked `nothrow`. The function must either take no arguments or a single argument of type `Resource`. Any value returned by the function is ignored.

Constructor & Destructor Documentation

◆ handle() [1/4]

template<typename Resource , Resource Closed, auto CloseFunc, std::enable_if_t< std::is_nothrow_copy_constructible_v< Resource > &&std::is_nothrow_swappable_v< Resource > &&std::is_function_v< std::remove_pointer_t< decltype(CloseFunc)> > &&(std::is_invocable_v< decltype(CloseFunc), Resource >||std::is_invocable_v< decltype(CloseFunc)>)> * = nullptr>

w::handle< Resource, Closed, CloseFunc, >::handle ( )

inlinenoexcept

Constructs a handle which does not own a resource.

◆ handle() [2/4]

template<typename Resource , Resource Closed, auto CloseFunc, std::enable_if_t< std::is_nothrow_copy_constructible_v< Resource > &&std::is_nothrow_swappable_v< Resource > &&std::is_function_v< std::remove_pointer_t< decltype(CloseFunc)> > &&(std::is_invocable_v< decltype(CloseFunc), Resource >||std::is_invocable_v< decltype(CloseFunc)>)> * = nullptr>

w::handle< Resource, Closed, CloseFunc, >::handle ( Resource resource )

inlinenoexcept

Constructs a handle which owns the specified resource.

Parameters

resource The resource to own.

◆ handle() [3/4]

template<typename Resource , Resource Closed, auto CloseFunc, std::enable_if_t< std::is_nothrow_copy_constructible_v< Resource > &&std::is_nothrow_swappable_v< Resource > &&std::is_function_v< std::remove_pointer_t< decltype(CloseFunc)> > &&(std::is_invocable_v< decltype(CloseFunc), Resource >||std::is_invocable_v< decltype(CloseFunc)>)> * = nullptr>

w::handle< Resource, Closed, CloseFunc, >::handle ( const handle< Resource, Closed, CloseFunc, > & )

delete

◆ handle() [4/4]

template<typename Resource , Resource Closed, auto CloseFunc, std::enable_if_t< std::is_nothrow_copy_constructible_v< Resource > &&std::is_nothrow_swappable_v< Resource > &&std::is_function_v< std::remove_pointer_t< decltype(CloseFunc)> > &&(std::is_invocable_v< decltype(CloseFunc), Resource >||std::is_invocable_v< decltype(CloseFunc)>)> * = nullptr>

w::handle< Resource, Closed, CloseFunc, >::handle ( handle< Resource, Closed, CloseFunc, > && other )

inlinenoexcept

Constructs a handle which takes ownership of a resource (if any) from another handle.

Parameters

other The other handle whose resource (if any) to take ownership of.

◆ ~handle()

template<typename Resource , Resource Closed, auto CloseFunc, std::enable_if_t< std::is_nothrow_copy_constructible_v< Resource > &&std::is_nothrow_swappable_v< Resource > &&std::is_function_v< std::remove_pointer_t< decltype(CloseFunc)> > &&(std::is_invocable_v< decltype(CloseFunc), Resource >||std::is_invocable_v< decltype(CloseFunc)>)> * = nullptr>

w::handle< Resource, Closed, CloseFunc, >::~handle ( )

inlinenoexcept

Closes the resource (if any) owned by this handle.

Member Function Documentation

◆ close()

template<typename Resource , Resource Closed, auto CloseFunc, std::enable_if_t< std::is_nothrow_copy_constructible_v< Resource > &&std::is_nothrow_swappable_v< Resource > &&std::is_function_v< std::remove_pointer_t< decltype(CloseFunc)> > &&(std::is_invocable_v< decltype(CloseFunc), Resource >||std::is_invocable_v< decltype(CloseFunc)>)> * = nullptr>

void w::handle< Resource, Closed, CloseFunc, >::close ( )

inlinenoexcept

Closes the resource (if any) owned by this handle by calling CloseFunc.

After the call, the handle no longer owns a resource. CloseFunc is only called if the handle owns a resource.

◆ get() [1/2]

template<typename Resource , Resource Closed, auto CloseFunc, std::enable_if_t< std::is_nothrow_copy_constructible_v< Resource > &&std::is_nothrow_swappable_v< Resource > &&std::is_function_v< std::remove_pointer_t< decltype(CloseFunc)> > &&(std::is_invocable_v< decltype(CloseFunc), Resource >||std::is_invocable_v< decltype(CloseFunc)>)> * = nullptr>

const Resource w::handle< Resource, Closed, CloseFunc, >::get ( ) const

inlinenoexcept

Returns the resource (if any) owned by this handle.

Returns: The owned resource, or the special value Closed if this handle does not own a resource.

◆ get() [2/2]

template<typename Resource , Resource Closed, auto CloseFunc, std::enable_if_t< std::is_nothrow_copy_constructible_v< Resource > &&std::is_nothrow_swappable_v< Resource > &&std::is_function_v< std::remove_pointer_t< decltype(CloseFunc)> > &&(std::is_invocable_v< decltype(CloseFunc), Resource >||std::is_invocable_v< decltype(CloseFunc)>)> * = nullptr>

Resource w::handle< Resource, Closed, CloseFunc, >::get ( )

inlinenoexcept

Returns the resource (if any) owned by this handle.

Returns: The owned resource, or the special value Closed if this handle does not own a resource.

◆ operator bool()

template<typename Resource , Resource Closed, auto CloseFunc, std::enable_if_t< std::is_nothrow_copy_constructible_v< Resource > &&std::is_nothrow_swappable_v< Resource > &&std::is_function_v< std::remove_pointer_t< decltype(CloseFunc)> > &&(std::is_invocable_v< decltype(CloseFunc), Resource >||std::is_invocable_v< decltype(CloseFunc)>)> * = nullptr>

w::handle< Resource, Closed, CloseFunc, >::operator bool ( ) const

inlinenoexcept

Tests whether this handle owns a resource.

Returns: true if this handle owns a resource.

◆ operator const Resource()

template<typename Resource , Resource Closed, auto CloseFunc, std::enable_if_t< std::is_nothrow_copy_constructible_v< Resource > &&std::is_nothrow_swappable_v< Resource > &&std::is_function_v< std::remove_pointer_t< decltype(CloseFunc)> > &&(std::is_invocable_v< decltype(CloseFunc), Resource >||std::is_invocable_v< decltype(CloseFunc)>)> * = nullptr>

w::handle< Resource, Closed, CloseFunc, >::operator const Resource ( ) const

inlinenoexcept

Returns the resource (if any) owned by this handle.

Returns: The owned resource, or the special value Closed if this handle does not own a resource.

◆ operator Resource()

template<typename Resource , Resource Closed, auto CloseFunc, std::enable_if_t< std::is_nothrow_copy_constructible_v< Resource > &&std::is_nothrow_swappable_v< Resource > &&std::is_function_v< std::remove_pointer_t< decltype(CloseFunc)> > &&(std::is_invocable_v< decltype(CloseFunc), Resource >||std::is_invocable_v< decltype(CloseFunc)>)> * = nullptr>

w::handle< Resource, Closed, CloseFunc, >::operator Resource ( )

inlinenoexcept

Returns the resource (if any) owned by this handle.

Returns: The owned resource, or the special value Closed if this handle does not own a resource.

◆ operator=() [1/2]

template<typename Resource , Resource Closed, auto CloseFunc, std::enable_if_t< std::is_nothrow_copy_constructible_v< Resource > &&std::is_nothrow_swappable_v< Resource > &&std::is_function_v< std::remove_pointer_t< decltype(CloseFunc)> > &&(std::is_invocable_v< decltype(CloseFunc), Resource >||std::is_invocable_v< decltype(CloseFunc)>)> * = nullptr>

handle & w::handle< Resource, Closed, CloseFunc, >::operator= ( const handle< Resource, Closed, CloseFunc, > & )

delete

◆ operator=() [2/2]

template<typename Resource , Resource Closed, auto CloseFunc, std::enable_if_t< std::is_nothrow_copy_constructible_v< Resource > &&std::is_nothrow_swappable_v< Resource > &&std::is_function_v< std::remove_pointer_t< decltype(CloseFunc)> > &&(std::is_invocable_v< decltype(CloseFunc), Resource >||std::is_invocable_v< decltype(CloseFunc)>)> * = nullptr>

handle & w::handle< Resource, Closed, CloseFunc, >::operator= ( handle< Resource, Closed, CloseFunc, > && other )

inlinenoexcept

Releases the resource (if any) owned by this handle and takes ownership of a resource (if any) from another handle.

Parameters

other The other handle whose resource (if any) to take ownership of.

Returns: A reference to this object.

◆ release()

template<typename Resource , Resource Closed, auto CloseFunc, std::enable_if_t< std::is_nothrow_copy_constructible_v< Resource > &&std::is_nothrow_swappable_v< Resource > &&std::is_function_v< std::remove_pointer_t< decltype(CloseFunc)> > &&(std::is_invocable_v< decltype(CloseFunc), Resource >||std::is_invocable_v< decltype(CloseFunc)>)> * = nullptr>

Resource w::handle< Resource, Closed, CloseFunc, >::release ( )

inlinenoexcept

Releases (without closing) and returns the underlying resource.

Returns: The underlying resource.

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

handle.hpp

Public Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ handle() [1/4]

◆ handle() [2/4]

◆ handle() [3/4]

◆ handle() [4/4]

◆ ~handle()

Member Function Documentation

◆ close()

◆ get() [1/2]

◆ get() [2/2]

◆ operator bool()

◆ operator const Resource()

◆ operator Resource()

◆ operator=() [1/2]

◆ operator=() [2/2]

◆ release()