C++: Difference between revisions

426 bytes added ,  28 October 2019
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Use <code>shared_ptr</code> when multiple objects need to reference the same thing.<br>
Use <code>shared_ptr</code> when multiple objects need to reference the same thing.<br>
Use <code>weak_ptr</code> to avoid cyclic dependencies which cause issues with reference counting.<br>
Use <code>weak_ptr</code> to avoid cyclic dependencies which cause issues with reference counting.<br>
If you are using C++14 or newer, you should use <code>make_unique</code> or <code>make_shared</code> which will only make one memory allocation for both the object and the pointer rather than two memory allocations.<br>
Alternatively if you already have a smart pointer, you can call <code>my_ptr.reset(new Car())</code> to change the pointer or <code>my_ptr.reset()</code> to deallocate the object referenced by the pointer.
Example:
Example:
<syntaxhighlight lang="cpp">
<syntaxhighlight lang="cpp">