Invoke.hxx File Reference

This header declares the invoke function to call function objects that may throw exceptions. More...

#include <optional>
#include <functional>
#include <type_traits>
#include "MGIS/Config.hxx"
#include "MGIS/InvalidResult.hxx"
#include "MGIS/Context.hxx"
#include "MGIS/Utilities/Invoke.ixx"

Namespaces
namespace	mgis
	the namespace mgis encloses all the MGIS project.

Macros
#define	MGIS_INVOKE(e, ...)   ::mgis::invoke(e, __VA_ARGS__)
	a simple wrapper around the invoke function which handles the declaration of the source location if needed
#define	MGIS_INVOKE_CHECK_ERRNO(e, ...)   ::mgis::invokeCheckErrno(e, __VA_ARGS__)
#define	MGIS_TRY_INVOKE_VOID(e, ...)
	a simple wrapper around the invoke function when the returned type of the callable is void
#define	MGIS_TRY_INVOKE_VOID_CHECK_ERRNO(e, ...)
#define	MGIS_TRY_INVOKE(v, e, ...)
	a simple wrapper around the invoke function
#define	MGIS_TRY_INVOKE_CHECK_ERRNO(v, e, ...)

Typedefs
template<typename F , typename... ArgumentsTypes>
using	mgis::invoke_result_t = std::conditional_t< std::is_void_v< std::invoke_result_t< F, ArgumentsTypes... > >, bool, std::optional< std::invoke_result_t< F, ArgumentsTypes... > > >
	a simple alias

Functions
template<typename F , typename... ArgumentsTypes>
invoke_result_t< F, ArgumentsTypes... >	mgis::invoke (Context &, F &&, ArgumentsTypes &&...) noexcept
	invoke the given callable object param[inout] ctx: execution context
template<typename F , typename... ArgumentsTypes>
invoke_result_t< F, ArgumentsTypes... >	mgis::invokeCheckErrno (Context &, F &&, ArgumentsTypes &&...) noexcept

Detailed Description

This header declares the invoke function to call function objects that may throw exceptions.

Date

07/11/2022

Macro Definition Documentation

MGIS_INVOKE

#define MGIS_INVOKE	(		e,
			...
	)		::mgis::invoke(e, __VA_ARGS__)

a simple wrapper around the invoke function which handles the declaration of the source location if needed

Parameters

[in,out]

ctx

execution context

Warning

If the function invoked has optional arguments (with default values), all the optional arguments must be provided, else the code will not compile with an obscure error message

Note

a version check the errno value while the other don't (names are self descriptive)

MGIS_TRY_INVOKE

#define MGIS_TRY_INVOKE	(		v,
			e,
			...
	)

Value:

  const auto MGIS_TEMPORARY_VARIABLE(v) = MGIS_INVOKE(e, __VA_ARGS__); \
  if (!MGIS_TEMPORARY_VARIABLE(v).hasValue()) {                        \
    return InvalidResult{};                                            \
  }                                                                    \
  auto &v = *(MGIS_TEMPORARY_VARIABLE(v));

a simple wrapper around the invoke function

Parameters

[in,out]	ctx	execution context
[out]	v	variable name which will contain the returned value of the function invoked. This variable is declared inside the macro and so must not be declared before.

Warning

If the function invoked has optional arguments (with default values), all the optional arguments must be provided, else the code will not compile with an obscure error message

Note

a version check the errno value while the other don't (names are self descriptive)

MGIS_TRY_INVOKE_CHECK_ERRNO

#define MGIS_TRY_INVOKE_CHECK_ERRNO	(		v,
			e,
			...
	)

Value:

  const auto MGIS_TEMPORARY_VARIABLE(v) =       \
      MGIS_INVOKE_CHECK_ERRNO(e, __VA_ARGS__);  \
  if (!MGIS_TEMPORARY_VARIABLE(v).hasValue()) { \
    return InvalidResult{};                     \
  }                                             \
  auto &v = *(MGIS_TEMPORARY_VARIABLE(v));

MGIS_TRY_INVOKE_VOID

#define MGIS_TRY_INVOKE_VOID	(		e,
			...
	)

Value:

  if (!MGIS_INVOKE(e, __VA_ARGS__)) { \
    return InvalidResult{};           \
  }

a simple wrapper around the invoke function when the returned type of the callable is void

Parameters

[in,out]

ctx

execution context

Warning

If the function invoked has optional arguments (with default values), all the optional arguments must be provided, else the code will not compile with an obscure error message

Note

a version check the errno value while the other don't (names are self descriptive)

MGIS_TRY_INVOKE_VOID_CHECK_ERRNO

#define MGIS_TRY_INVOKE_VOID_CHECK_ERRNO	(		e,
			...
	)

Value:

  if (!MGIS_INVOKE_CHECK_ERRNO(e, __VA_ARGS__)) { \
    return InvalidResult{};                       \
  }