wxwidgets/interface/wx/scopeguard.h
Vadim Zeitlin 4f4c5fcfdf Use nullptr instead of NULL in the code and documentation
This is a combination of running clang-tidy with modernize-use-nullptr
check for some ports (GTK, X11, OSX) and manual changes to the ports for
which it couldn't be used easily (MSW, DFB) and also manually updating
the docs.

Also replace NULL with null or nullptr in the comments as this is more
consistent with the use of nullptr in the code and makes it simpler to
grep for the remaining occurrences of NULL itself.

And also use null in the assert messages.

Only a few occurrences of "NULL" are still left in non-C files, mostly
corresponding to unclear comments or string output which it might not be
safe to change.
2022-10-18 01:25:25 +02:00

153 lines
4.2 KiB
Objective-C

/////////////////////////////////////////////////////////////////////////////
// Name: scopeguard.h
// Purpose: interface of global functions
// Author: wxWidgets team
// Licence: wxWindows licence
/////////////////////////////////////////////////////////////////////////////
/**
@class wxScopeGuard
Scope guard is an object which allows executing an action on scope exit.
The objects of this class must be constructed using wxMakeGuard() function.
@nolibrary
@category{misc}
*/
class wxScopeGuard
{
public:
/**
Call this method to dismiss the execution of the action on scope exit.
A typical example:
@code
Update1();
// ensure that changes done so far are rolled back if the next
// operation throws
wxScopeGuard guard = wxMakeGuard(RollBack);
Update2();
// it didn't throw so commit the changes, i.e. avoid rolling back
guard.Dismiss();
@endcode
*/
void Dismiss();
};
/** @addtogroup group_funcmacro_misc */
///@{
/**
Returns a scope guard object which will call the specified function with
the given parameters on scope exit.
This function is overloaded to take several parameters up to some
implementation-defined (but relatively low) limit.
The @a func should be a functor taking parameters of the types P1, ..., PN,
i.e. the expression @c func(p1, ..., pN) should be valid.
*/
template <typename F, typename P1, ..., typename PN>
wxScopeGuard wxMakeGuard(F func, P1 p1, ..., PN pN);
///@}
/** @addtogroup group_funcmacro_misc */
///@{
/**
Ensure that the global @a function with a few (up to some
implementation-defined limit) is executed on scope exit, whether due to a
normal function return or because an exception has been thrown.
A typical example of its usage:
@code
void *buf = malloc(size);
wxON_BLOCK_EXIT1(free, buf);
@endcode
Please see the original article by Andrei Alexandrescu and Petru Marginean
published in December 2000 issue of C/C++ Users Journal for more details.
@see wxON_BLOCK_EXIT_OBJ0()
@header{wx/scopeguard.h}
*/
#define wxON_BLOCK_EXIT(function, ...)
#define wxON_BLOCK_EXIT0(function)
#define wxON_BLOCK_EXIT1(function, p1)
#define wxON_BLOCK_EXIT2(function, p1, p2)
#define wxON_BLOCK_EXIT3(function, p1, p2, p3)
///@}
/** @addtogroup group_funcmacro_misc */
///@{
/**
This family of macros is similar to wxON_BLOCK_EXIT(), but calls a method
of the given object instead of a free function.
@header{wx/scopeguard.h}
*/
#define wxON_BLOCK_EXIT_OBJ(object, method, ...)
#define wxON_BLOCK_EXIT_OBJ0(object, method)
#define wxON_BLOCK_EXIT_OBJ1(object, method, p1)
#define wxON_BLOCK_EXIT_OBJ2(object, method, p1, p2)
#define wxON_BLOCK_EXIT_OBJ3(object, method, p1, p2, p3)
///@}
/** @addtogroup group_funcmacro_misc */
///@{
/**
This family of macros is similar to wxON_BLOCK_OBJ(), but calls a method
of @c this object instead of a method of the specified object.
@header{wx/scopeguard.h}
*/
#define wxON_BLOCK_EXIT_THIS(method, ...)
#define wxON_BLOCK_EXIT_THIS0(method)
#define wxON_BLOCK_EXIT_THIS1(method, p1)
#define wxON_BLOCK_EXIT_THIS2(method, p1, p2)
#define wxON_BLOCK_EXIT_THIS3(method, p1, p2, p3)
///@}
/** @addtogroup group_funcmacro_misc */
///@{
/**
This macro sets a variable to the specified value on scope exit.
Example of usage:
@code
void foo()
{
bool isDoingSomething = true;
{
wxON_BLOCK_EXIT_SET(isDoingSomething, false);
... do something ...
}
... isDoingSomething is false now ...
}
@endcode
Notice that @a value is copied, i.e. stored by value, so it can be a
temporary object returned by a function call, for example.
@see wxON_BLOCK_EXIT_OBJ0(), wxON_BLOCK_EXIT_NULL()
@header{wx/scopeguard.h}
*/
#define wxON_BLOCK_EXIT_SET(var, value)
/**
This macro sets the pointer passed to it as argument to @NULL on scope exit.
It may be used instead of wxON_BLOCK_EXIT_SET() when the value being set
is @NULL.
@header{wx/scopeguard.h}
*/
#define wxON_BLOCK_EXIT_NULL(ptr)
///@}