How does the custom deleter of std::unique_ptr work?

Question

According to N3290, std::unique_ptr accepts a deleter argument in its constructor.

However, I can\'t get that to work with Visual C++ 10.0 or MinGW g++

Answer 1

To complement all previous answers, there is a way to have a custom deleter without having to "pollute" the unique_ptr signature by having either a function pointer or something equivalent in it like this:

std::unique_ptr< MyType, myTypeDeleter > // not pretty

This is achievable by providing a specialization to the std::default_delete template class, like this:

namespace std
{
template<>
class default_delete< MyType >
{
public:
  void operator()(MyType *ptr)
  {
    delete ptr;
  }
};
}

And now all std::unique_ptr< MyType > that "sees" this specialization will be deleted with it. Just be aware that it might not be what you want for all std::unique_ptr< MyType >, so chose carefully your solution.