Why would a new[] expression ever invoke a destructor?












8















From the C++17 standard (draft here), [expr.new]:




If the new-expression creates an object or an array of objects of class type, access and ambiguity control are done for the allocation function, the deallocation function, and the constructor. If the new-expression creates an array of objects of class type, the destructor is potentially invoked.




Why would new invoke a destructor? It's new, after all. It isn't delete.






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    8















    From the C++17 standard (draft here), [expr.new]:




    If the new-expression creates an object or an array of objects of class type, access and ambiguity control are done for the allocation function, the deallocation function, and the constructor. If the new-expression creates an array of objects of class type, the destructor is potentially invoked.




    Why would new invoke a destructor? It's new, after all. It isn't delete.






    c++ c++17 new-operator







    share|improve this question



























      8












      8








      8








      From the C++17 standard (draft here), [expr.new]:




      If the new-expression creates an object or an array of objects of class type, access and ambiguity control are done for the allocation function, the deallocation function, and the constructor. If the new-expression creates an array of objects of class type, the destructor is potentially invoked.




      Why would new invoke a destructor? It's new, after all. It isn't delete.






      c++ c++17 new-operator







      share|improve this question
















      From the C++17 standard (draft here), [expr.new]:




      If the new-expression creates an object or an array of objects of class type, access and ambiguity control are done for the allocation function, the deallocation function, and the constructor. If the new-expression creates an array of objects of class type, the destructor is potentially invoked.




      Why would new invoke a destructor? It's new, after all. It isn't delete.






      c++ c++17 new-operator




      c++ c++17 new-operator






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      edited 2 hours ago









      Cody Gray♦

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      195k35382470










      asked 2 hours ago









      thbthb

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      8,66932355
























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          If construction of any object in the buffer throws an exception, the previously constructed objects must be destructed. That requires an available destructor.






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            If construction of any object in the buffer throws an exception, the previously constructed objects must be destructed. That requires an available destructor.






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              15














              If construction of any object in the buffer throws an exception, the previously constructed objects must be destructed. That requires an available destructor.






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                If construction of any object in the buffer throws an exception, the previously constructed objects must be destructed. That requires an available destructor.






                share|improve this answer















                If construction of any object in the buffer throws an exception, the previously constructed objects must be destructed. That requires an available destructor.







                share|improve this answer














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                StoryTellerStoryTeller

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