alpha
/
Kaleidoscope
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Introduced has_method.h traits

Browse Source 
A traits class that is used to check if a class implements a
method with a given signature was already used by
the eventhandler signature check. It has now been moved to
its own traits header (macro name is DEFINE_HAS_METHOD_TRAITS).

Signed-off-by: Florian Fleissner <florian.fleissner@inpartik.de>
pull/617/head
Florian Fleissner 6 years ago
parent 8fe381a0a2
commit af1c2ba659
2 changed files with 84 additions and 47 deletions
Show Stats Download Patch File Download Diff File

58
src/kaleidoscope_internal/eventhandler_signature_check.h
Unescape View File

@ -19,6 +19,7 @@
#include "kaleidoscope/macro_helpers.h"
#include "kaleidoscope/plugin.h"
#include "kaleidoscope_internal/type_traits/has_member.h"
#include "kaleidoscope_internal/type_traits/has_method.h"
// *************************************************************************
// *************************************************************************
@ -92,59 +93,22 @@ template<typename Plugin__> struct
#define _DEFINE_IMPLEMENTATION_CHECK_CLASS_SPECIALIZATION( \
HOOK_NAME, HOOK_VERSION, DEPRECATION_TAG, \
SHOULD_ABORT_ON_CONSUMED_EVENT, SIGNATURE, ARGS_LIST) \
\
/* We use the generalized traits class found in header has_method.h __NL__ \
* to do check if a plugin defines a hook method with a specific __NL__ \
* signature. __NL__ \
*/ __NL__ \
DEFINE_HAS_METHOD_TRAITS(Plugin, HOOK_NAME, __NL__ \
kaleidoscope::EventHandlerResult, __NL__ \
SIGNATURE) __NL__ \
__NL__ \
/* This specialization checks if a plugin of type Plugin__ __NL__ \
* implements a handler with given signature SIGNATURE. __NL__ \
*/ __NL__ \
template<typename Plugin__> __NL__ \
struct HookVersionImplemented_##HOOK_NAME<Plugin__, HOOK_VERSION> __NL__ \
{ __NL__ \
/* Define a pointer to member function with the correct __NL__ \
* argument signature. The newly defined type is named __NL__ \
* HookType__. __NL__ \
*/ __NL__ \
typedef kaleidoscope::EventHandlerResult __NL__ \
(Plugin__::*HookType__)SIGNATURE; __NL__ \
__NL__ \
/* See the definition of HookIimplemented_##HOOK_NAME above __NL__ \
* for an explanation of the SFINAE concept that is applied here. __NL__ \
* The difference to the afforementioned class is that __NL__ \
* here we check if a specific version of a handler was __NL__ \
* implemented. This is done by forcing the compiler __NL__ \
* through a static cast to select the respective method __NL__ \
* if possible. If the method signature cannot be found, __NL__ \
* the substitution fails and the first version of method "test" __NL__ \
* will not be defined. __NL__ \
*/ __NL__ \
template <typename PluginAux__> __NL__ \
static constexpr __NL__ \
/* The following decltype-clause defines the function return type __NL__ \
*/ __NL__ \
decltype( __NL__ \
/* If &PluginAux__::HOOK_NAME exists and is of type __NL__ \
* HookType__, the list below evaluates to bool{} whose __NL__ \
* type can be determined. Otherwise the comma expression __NL__ \
* cannot be evaluated and the content __NL__ \
* of decltype is undefined and this function overload __NL__ \
* is ignored by the compiler __NL__ \
* (SFINAE = substitution failure is not an error) __NL__ \
* and the test(...) overload is used instead. __NL__ \
*/ __NL__ \
static_cast<HookType__>(&PluginAux__::HOOK_NAME), bool{} __NL__ \
) __NL__ \
test(int /* unused */) __NL__ \
{ __NL__ \
return true; __NL__ \
} __NL__ \
__NL__ \
template <typename PluginAux__> __NL__ \
static constexpr bool test(...) __NL__ \
{ __NL__ \
return false; __NL__ \
} __NL__ \
__NL__ \
static constexpr bool value = test<Plugin__>(int{}); __NL__ \
};
: public Plugin_HasMethod_##HOOK_NAME<Plugin__> __NL__ \
{};
#define _PREPARE_EVENT_HANDLER_SIGNATURE_CHECK_START(HOOK_NAME, ...) \
__NL__ \

73
src/kaleidoscope_internal/type_traits/has_method.h
Unescape View File

@ -0,0 +1,73 @@
/* Kaleidoscope - Firmware for computer input devices
* Copyright (C) 2013-2018 Keyboard.io, Inc.
*
* This program is free software: you can redistribute it and/or modify it under
* the terms of the GNU General Public License as published by the Free Software
* Foundation, version 3.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
* FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
* details.
*
* You should have received a copy of the GNU General Public License along with
* this program. If not, see <http://www.gnu.org/licenses/>.
*/
#pragma once
#include "kaleidoscope/macro_helpers.h"
#define DEFINE_HAS_METHOD_TRAITS(PREFIX, METHOD_NAME, \
RETURN_TYPE, ARGUMENTS) \
__NL__ \
/* This traits checks if a class of type Class__ __NL__ \
* implements a method with given signature. __NL__ \
*/ __NL__ \
template<typename Class__> __NL__ \
struct PREFIX##_HasMethod_##METHOD_NAME __NL__ \
{ __NL__ \
/* Define a pointer to member function with the correct __NL__ \
* argument signature. The newly defined type is named __NL__ \
* MethodType__. __NL__ \
*/ __NL__ \
typedef RETURN_TYPE (Class__::*MethodType__)ARGUMENTS; __NL__ \
__NL__ \
/* This is an application of the SFINAE concept. __NL__ \
* We check if Class__ defines a method with given name and __NL__ \
* signature. This is done by forcing the compiler __NL__ \
* through a static cast to select the respective method __NL__ \
* if possible. If the method signature cannot be found, __NL__ \
* the substitution fails and the first version of method "test" __NL__ \
* will not be defined. __NL__ \
*/ __NL__ \
template <typename ClassAux__> __NL__ \
static constexpr __NL__ \
/* The following decltype-clause defines the function return type __NL__ \
*/ __NL__ \
decltype( __NL__ \
/* If &ClassAux__::METHOD_NAME exists and is of type __NL__ \
* MethodType__, the list below evaluates to bool{} whose __NL__ \
* type can be determined. Otherwise the comma expression __NL__ \
* cannot be evaluated and the content __NL__ \
* of decltype is undefined and this function overload __NL__ \
* is ignored by the compiler __NL__ \
* (SFINAE = substitution failure is not an error) __NL__ \
* and the test(...) overload is used instead. __NL__ \
*/ __NL__ \
static_cast<MethodType__>(&ClassAux__::METHOD_NAME), bool{} __NL__ \
) __NL__ \
test(int /* unused */) __NL__ \
{ __NL__ \
return true; __NL__ \
} __NL__ \
__NL__ \
template <typename ClassAux__> __NL__ \
static constexpr bool test(...) __NL__ \
{ __NL__ \
return false; __NL__ \
} __NL__ \
__NL__ \
static constexpr bool value = test<Class__>(int{}); __NL__ \
};
Write Preview
Loading…
Cancel
Save