164 lines
3.8 KiB
C++
164 lines
3.8 KiB
C++
/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
|
|
//
|
|
// TGUI - Texus' Graphical User Interface
|
|
// Copyright (C) 2012-2019 Bruno Van de Velde (vdv_b@tgui.eu)
|
|
//
|
|
// This software is provided 'as-is', without any express or implied warranty.
|
|
// In no event will the authors be held liable for any damages arising from the use of this software.
|
|
//
|
|
// Permission is granted to anyone to use this software for any purpose,
|
|
// including commercial applications, and to alter it and redistribute it freely,
|
|
// subject to the following restrictions:
|
|
//
|
|
// 1. The origin of this software must not be misrepresented;
|
|
// you must not claim that you wrote the original software.
|
|
// If you use this software in a product, an acknowledgment
|
|
// in the product documentation would be appreciated but is not required.
|
|
//
|
|
// 2. Altered source versions must be plainly marked as such,
|
|
// and must not be misrepresented as being the original software.
|
|
//
|
|
// 3. This notice may not be removed or altered from any source distribution.
|
|
//
|
|
/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
|
|
|
|
// Code based on http://codereview.stackexchange.com/questions/20058/c11-any-class
|
|
|
|
#ifndef TGUI_ANY_HPP
|
|
#define TGUI_ANY_HPP
|
|
|
|
#include <type_traits>
|
|
#include <utility>
|
|
#include <typeinfo>
|
|
|
|
namespace tgui
|
|
{
|
|
struct Any
|
|
{
|
|
template<class T>
|
|
using StorageType = typename std::decay<T>::type;
|
|
|
|
bool is_null() const
|
|
{
|
|
return ptr == nullptr;
|
|
}
|
|
|
|
bool not_null() const
|
|
{
|
|
return ptr != nullptr;
|
|
}
|
|
|
|
template<typename U>
|
|
Any(U&& value)
|
|
: ptr{new Derived<StorageType<U>>(std::forward<U>(value))}
|
|
{
|
|
}
|
|
|
|
template<class U>
|
|
bool is() const
|
|
{
|
|
typedef StorageType<U> T;
|
|
return dynamic_cast<Derived<T>*>(ptr);
|
|
}
|
|
|
|
template<class U>
|
|
StorageType<U>& as() const
|
|
{
|
|
typedef StorageType<U> T;
|
|
auto derived = dynamic_cast<Derived<T>*>(ptr);
|
|
if (!derived)
|
|
throw std::bad_cast();
|
|
|
|
return derived->value;
|
|
}
|
|
|
|
template<class U>
|
|
operator U()
|
|
{
|
|
return as<StorageType<U>>();
|
|
}
|
|
|
|
Any()
|
|
: ptr(nullptr)
|
|
{
|
|
}
|
|
|
|
Any(const Any& that)
|
|
: ptr(that.clone())
|
|
{
|
|
}
|
|
|
|
Any(Any&& that)
|
|
: ptr(that.ptr)
|
|
{
|
|
that.ptr = nullptr;
|
|
}
|
|
|
|
Any& operator=(const Any& a)
|
|
{
|
|
if (ptr == a.ptr)
|
|
return *this;
|
|
|
|
auto old_ptr = ptr;
|
|
|
|
ptr = a.clone();
|
|
|
|
if (old_ptr)
|
|
delete old_ptr;
|
|
|
|
return *this;
|
|
}
|
|
|
|
Any& operator=(Any&& a)
|
|
{
|
|
if (ptr == a.ptr)
|
|
return *this;
|
|
|
|
std::swap(ptr, a.ptr);
|
|
|
|
return *this;
|
|
}
|
|
|
|
~Any()
|
|
{
|
|
delete ptr;
|
|
}
|
|
|
|
private:
|
|
struct Base
|
|
{
|
|
virtual ~Base() {}
|
|
virtual Base* clone() const = 0;
|
|
};
|
|
|
|
template<typename T>
|
|
struct Derived : Base
|
|
{
|
|
template<typename U>
|
|
Derived(U&& val) :
|
|
value(std::forward<U>(val))
|
|
{
|
|
}
|
|
|
|
Base* clone() const override
|
|
{
|
|
return new Derived<T>(value);
|
|
}
|
|
|
|
T value;
|
|
};
|
|
|
|
Base* clone() const
|
|
{
|
|
if (ptr)
|
|
return ptr->clone();
|
|
else
|
|
return nullptr;
|
|
}
|
|
|
|
Base* ptr;
|
|
};
|
|
}
|
|
|
|
#endif // TGUI_ANY_HPP
|