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