#pragma once
#include "megbrain/utils/thin/function.h"
namespace mgb {
namespace imperative {
template <typename TFunction>
class FunctionHook;
template <template <typename> class TFunction, typename TRet, typename... TArgs>
class FunctionHook<TFunction<TRet(TArgs...)>> {
public:
using FunctionType = TFunction<TRet(TArgs...)>;
explicit FunctionHook(FunctionType* fptr) : m_fptr{fptr} { m_backup = *fptr; }
public:
template <
typename THook,
typename = std::enable_if_t<
std::is_invocable_r_v<TRet, THook, FunctionType, TArgs...>, void>>
FunctionHook& apply_hook(THook&& hook) {
*m_fptr = [func = *m_fptr,
hook = std::forward<THook>(hook)](TArgs... args) -> TRet {
return hook(func, std::forward<TArgs>(args)...);
};
return *this;
}
private:
FunctionType* m_fptr;
FunctionType m_backup;
public:
~FunctionHook() { *m_fptr = std::move(m_backup); }
};
template <typename TFunction>
auto make_shared_hook(TFunction* fptr) {
return std::make_shared<FunctionHook<TFunction>>(fptr);
}
} }