tachyon::Result< T > Class Template Reference

A value, or the Error saying why there is none. More...

#include <gui_core/gui_result.h>

Public Member Functions
	Result (T value)
	Implicit from a value or an Error, so functions can return either.
	Result (Error error)
bool	HasValue () const
	True when it holds the value; same as the bool conversion.
	operator bool () const
T	ValueOr (T fallback) const
	A copy of the value, or fallback when there is none.
const Error &	GetError () const
	The error; only valid when !HasValue().
T &	Value ()
	The value; only valid when HasValue() (std::get throws otherwise).
const T &	Value () const
	The value; only valid when HasValue() (std::get throws otherwise).
T &	operator* ()
	The value; only valid when HasValue() (std::get throws otherwise).
const T &	operator* () const
	The value; only valid when HasValue() (std::get throws otherwise).
T *	operator-> ()
	The value; only valid when HasValue() (std::get throws otherwise).
const T *	operator-> () const
	The value; only valid when HasValue() (std::get throws otherwise).

Detailed Description

template<class T>
class tachyon::Result< T >

A value, or the Error saying why there is none.

True when it holds the value:

if (auto image = LoadImage(path)) Use(*image); else Log(image.GetError().message); 

Examples

controls/controls.cpp, custom_theme/custom_theme.cpp, docking/docking.cpp, hello_world/hello_world.cpp, and host_device/host_device.cpp.

Member Function Documentation

HasValue()

template<class T>

bool tachyon::Result< T >::HasValue ( ) const

inline

True when it holds the value; same as the bool conversion.

operator bool()

template<class T>

tachyon::Result< T >::operator bool ( ) const

inlineexplicit

Value() [1/2]

template<class T>

T & tachyon::Result< T >::Value ( )

inline

The value; only valid when HasValue() (std::get throws otherwise).

• and -> do the same.

Value() [2/2]

template<class T>

const T & tachyon::Result< T >::Value ( ) const

inline

The value; only valid when HasValue() (std::get throws otherwise).

• and -> do the same.

operator*() [1/2]

template<class T>

T & tachyon::Result< T >::operator* ( )

inline

The value; only valid when HasValue() (std::get throws otherwise).

• and -> do the same.

operator*() [2/2]

template<class T>

const T & tachyon::Result< T >::operator* ( ) const

inline

The value; only valid when HasValue() (std::get throws otherwise).

• and -> do the same.

operator->() [1/2]

template<class T>

T * tachyon::Result< T >::operator-> ( )

inline

The value; only valid when HasValue() (std::get throws otherwise).

• and -> do the same.

operator->() [2/2]

template<class T>

const T * tachyon::Result< T >::operator-> ( ) const

inline

The value; only valid when HasValue() (std::get throws otherwise).

• and -> do the same.

ValueOr()

template<class T>

T tachyon::Result< T >::ValueOr ( T fallback ) const

inline

A copy of the value, or fallback when there is none.

GetError()

template<class T>

const Error & tachyon::Result< T >::GetError ( ) const

inline

The error; only valid when !HasValue().

Examples

controls/controls.cpp, custom_theme/custom_theme.cpp, docking/docking.cpp, hello_world/hello_world.cpp, and host_device/host_device.cpp.

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

• gui_core/gui_result.h