#pragma once
|
|
#include "gp/exception.hpp"
|
|
|
|
namespace gp{
|
|
|
|
template <typename>
|
|
class function;
|
|
|
|
template <typename ret, typename ...args>
|
|
class function<ret(args...)>{
|
|
struct virtual_callable
|
|
{
|
|
virtual ~virtual_callable() = default;
|
|
virtual ret operator() (args...) = 0;
|
|
};
|
|
|
|
template<typename fn>
|
|
class callable : public virtual_callable{
|
|
fn internal_representation;
|
|
public:
|
|
callable(const fn& func)
|
|
: internal_representation{func}
|
|
{}
|
|
|
|
virtual ~callable() override = default;
|
|
|
|
ret operator() (args... arg_list) override
|
|
{
|
|
return internal_representation(arg_list...);
|
|
}
|
|
};
|
|
|
|
enum state_t : uint8_t{
|
|
INACTIVE = 0,
|
|
ACTIVE = 1,
|
|
NO_SOO = 0,
|
|
SOO = 2
|
|
};
|
|
|
|
state_t state{};
|
|
union{
|
|
virtual_callable* functor = nullptr;
|
|
char inplace[12];
|
|
} self;
|
|
|
|
public:
|
|
template <typename T>
|
|
function& operator=(T& t)
|
|
{
|
|
if(state & ACTIVE)
|
|
{
|
|
if(state & SOO)
|
|
{
|
|
((virtual_callable*)&self)->~virtual_callable();
|
|
}
|
|
else
|
|
{
|
|
delete self.functor;
|
|
}
|
|
}
|
|
if constexpr (sizeof(callable<T>) <= sizeof(self))
|
|
{
|
|
new((void*)&self) callable(t);
|
|
state = (state_t)(ACTIVE | SOO);
|
|
}
|
|
else
|
|
{
|
|
self = new callable(t);
|
|
state = (state_t)(ACTIVE | NO_SOO);
|
|
}
|
|
}
|
|
|
|
function()
|
|
{
|
|
state = INACTIVE;
|
|
}
|
|
|
|
template <typename T>
|
|
function(T t)
|
|
{
|
|
if constexpr (sizeof(callable<T>) <= sizeof(self))
|
|
{
|
|
new((void*)&self) callable<T>(t);
|
|
state = (state_t)(ACTIVE | SOO);
|
|
}
|
|
else
|
|
{
|
|
self = new callable<T>(t);
|
|
state = (state_t)(ACTIVE | NO_SOO);
|
|
}
|
|
}
|
|
|
|
template <typename T>
|
|
function(T& t)
|
|
{
|
|
if constexpr (sizeof(callable<T>) <= sizeof(self))
|
|
{
|
|
new((void*)&self) callable<T>(t);
|
|
state = (state_t)(ACTIVE | SOO);
|
|
}
|
|
else
|
|
{
|
|
self.functor = new callable<T>(t);
|
|
state = (state_t)(ACTIVE | NO_SOO);
|
|
}
|
|
}
|
|
|
|
ret operator()(args... arg_list) const {
|
|
if constexpr (gp_config::has_exceptions)
|
|
{
|
|
if(!(state & ACTIVE))
|
|
{
|
|
throw bad_functor{};
|
|
}
|
|
}
|
|
if(state & SOO)
|
|
{
|
|
return (*(virtual_callable*)&self)(arg_list...);
|
|
}
|
|
else
|
|
{
|
|
return (*(self.functor))(arg_list...);
|
|
}
|
|
|
|
}
|
|
|
|
~function()
|
|
{
|
|
if(state & ACTIVE)
|
|
{
|
|
if(state & SOO)
|
|
{
|
|
((virtual_callable*)&self)->~virtual_callable();
|
|
}
|
|
else
|
|
{
|
|
delete self.functor;
|
|
}
|
|
}
|
|
|
|
}
|
|
};
|
|
|
|
}
|