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Difference between &(*similarObject) and similarObject? Are they not same?

开发者 https://www.devze.com 2023-03-26 08:44 出处:网络
Can someone please explain t开发者_如何学JAVAhis to me dynamic_cast<SomeObject *>( &(*similarObject) );

Can someone please explain t开发者_如何学JAVAhis to me

dynamic_cast<SomeObject *>( &(*similarObject) );

What is the point of doing the address of a dereferenced pointer? Wouldn’t the pointer itself just be the address of it?


It may be that the type of similarObject has overloaded operator* and so it returns something whose address you're passing to dynamic_cast.

&(*x) and x may not be always the same thing. For example, think of iterator:

std::map<int, int>::iterator it = v.begin();

Then it and &(*it) are two different thing:

  • The type of it is std::map<int, int>::iterator
  • The type of &(*it) is std::pair<int,int>*

They're not at all same. Similar thing may happen with your code-snippet as well.


If similarObject is a smart pointer, this technique is sometimes used to get the reference of a raw pointer, when * has been overloaded.


Nobody mentioned yet that similarObject is an lvalue, whereas &*similarObject is an rvalue.

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