std::numpunct::~numpunct
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                    | Defined in header  <locale> | ||
| protected: ~numpunct(); | ||
Destructs a std::numpunct facet. This destructor is protected and virtual (due to base class destructor being virtual). An object of type std::numpunct, like most facets, can only be destroyed when the last std::locale object that implements this facet goes out of scope or if a user-defined class is derived from std::numpunct and implements a public destructor.
[edit] Example
#include <iostream> #include <locale> struct Destructible_numpunct : public std::numpunct<wchar_t> { Destructible_numpunct(std::size_t refs = 0) : numpunct(refs) {} ~Destructible_numpunct() {}; // public dtor }; int main() { Destructible_numpunct dc; // std::numpunct<wchar_t> c; // compile error: protected destructor }