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wxScopedPtr

This is a simple scoped smart pointer implementation that is similar to the Boost smart pointers but rewritten to use macros instead.

Example

Below is an example of using a wxWindows scoped smart pointer and pointer array.

  class MyClass { /* ... */ };

  // declare a smart pointer to a MyClass called wxMyClassPtr
  wxDECLARE_SCOPED_PTR(MyClass, wxMyClassPtr)
  // declare a smart pointer to an array of chars
  wxDECLARE_SCOPED_ARRAY(char, wxCharArray)

  ...

  // define the first pointer class, must be complete
  wxDEFINE_SCOPED_PTR(MyClass, wxMyClassPtr)
  // define the second pointer class
  wxDEFINE_SCOPED_ARRAY(char, wxCharArray)

  // create an object with a new pointer to MyClass
  wxMyClassPtr theObj(new MyClass());
  // reset the pointer (deletes the previous one)
  theObj.reset(new MyClass());

  // access the pointer
  theObj->MyFunc();

  // create an object with a new array of chars
  wxCharArray theCharObj(new char[100]);

  // access the array
  theCharObj[0] = "!";
Declaring new smart pointer types

    wxDECLAR_SCOPED_PTR( TYPE,     // type of the values
                                CLASSNAME ); // name of the class
A smart pointer holds a pointer to an object (which must be complete when wxDEFINE_SCOPED_PTR() is called). The memory used by the object is deleted when the smart pointer goes out of scope. The first argument of the macro is the pointer type, the second is the name of the new smart pointer class being created. Below we will use wxScopedPtr to represent the scoped pointer class, but the user may create the class with any legal name.

Include files

<wx/ptr_scpd.h>

See also

wxScopedArray

Members

wxScopedPtr::wxScopedPtr
wxScopedPtr::reset
wxScopedPtr::operator *
wxScopedPtr::operator ->
wxScopedPtr::get
wxScopedPtr::swap


wxScopedPtr::wxScopedPtr

wxScopedPtr(type * T = NULL)

Creates the smart pointer with the given pointer or none if NULL. On compilers that support it, this uses the explicit keyword.


wxScopedPtr::reset

reset(T p * = NULL)

Deletes the currently held pointer and sets it to 'p' or to NULL if no arguments are specified. This function does check to make sure that the pointer you are assigning is not the same pointer that is already stored.


wxScopedPtr::operator *

const T& operator *()

This operator works like the standard C++ pointer operator to return the object being pointed to by the pointer. If the pointer is NULL or invalid this will crash.


wxScopedPtr::operator ->

const T* operator ->()

This operator works like the standard C++ pointer operator to return the pointer in the smart pointer or NULL if it is empty.


wxScopedPtr::get

const T* get()

This operator gets the pointer stored in the smart pointer or returns NULL if there is none.


wxScopedPtr::swap

swap(wxScopedPtr & ot)

Swap the pointer inside the smart pointer with 'ot'. The pointer being swapped must be of the same type (hence the same class name).