sustaining_gazes/lib/3rdParty/dlib/include/dlib/any/any.h
2016-04-28 15:40:36 -04:00

181 lines
3.7 KiB
C++

// Copyright (C) 2010 Davis E. King (davis@dlib.net)
// License: Boost Software License See LICENSE.txt for the full license.
#ifndef DLIB_AnY_H_
#define DLIB_AnY_H_
#include "any_abstract.h"
#include "../smart_pointers.h"
#include <typeinfo>
namespace dlib
{
// ----------------------------------------------------------------------------------------
class bad_any_cast : public std::bad_cast
{
public:
virtual const char * what() const throw()
{
return "bad_any_cast";
}
};
// ----------------------------------------------------------------------------------------
class any
{
public:
any()
{
}
any (
const any& item
)
{
if (item.data)
{
item.data->copy_to(data);
}
}
template <typename T>
any (
const T& item
)
{
typedef typename basic_type<T>::type U;
data.reset(new derived<U>(item));
}
void clear (
)
{
data.reset();
}
template <typename T>
bool contains (
) const
{
typedef typename basic_type<T>::type U;
return dynamic_cast<derived<U>*>(data.get()) != 0;
}
bool is_empty(
) const
{
return data.get() == 0;
}
template <typename T>
T& cast_to(
)
{
typedef typename basic_type<T>::type U;
derived<U>* d = dynamic_cast<derived<U>*>(data.get());
if (d == 0)
{
throw bad_any_cast();
}
return d->item;
}
template <typename T>
const T& cast_to(
) const
{
typedef typename basic_type<T>::type U;
derived<U>* d = dynamic_cast<derived<U>*>(data.get());
if (d == 0)
{
throw bad_any_cast();
}
return d->item;
}
template <typename T>
T& get(
)
{
typedef typename basic_type<T>::type U;
derived<U>* d = dynamic_cast<derived<U>*>(data.get());
if (d == 0)
{
d = new derived<U>();
data.reset(d);
}
return d->item;
}
any& operator= (
const any& item
)
{
any(item).swap(*this);
return *this;
}
void swap (
any& item
)
{
data.swap(item.data);
}
private:
struct base
{
virtual ~base() {}
virtual void copy_to (
scoped_ptr<base>& dest
) const = 0;
};
template <typename T>
struct derived : public base
{
T item;
derived() {}
derived(const T& val) : item(val) {}
virtual void copy_to (
scoped_ptr<base>& dest
) const
{
dest.reset(new derived<T>(item));
}
};
scoped_ptr<base> data;
};
// ----------------------------------------------------------------------------------------
inline void swap (
any& a,
any& b
) { a.swap(b); }
// ----------------------------------------------------------------------------------------
template <typename T> T& any_cast(any& a) { return a.cast_to<T>(); }
template <typename T> const T& any_cast(const any& a) { return a.cast_to<T>(); }
// ----------------------------------------------------------------------------------------
}
#endif // DLIB_AnY_H_