Re: [Boost-users] [optional]

2009/5/6 dariomt

Roman Perepelitsa writes:

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2009/5/6 Roman Perepelitsa It's less efficient, because all arguments will be copied. It's also more

typing, longer compilation times and more code generated.

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There is one more caveat. This approach does not work with polymorphic

types (you'll get slicing). I don't think there are any advantages in passing boost::optional<T> compared to const T*.Roman Perepelitsa.

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Thanks for the answer!

Is there a way to avoid the copy (and thus the slicing)? Perhaps using boost::optional or boost::optional< boost::reference_wrapper<T> > ?

You can use boost::optional, but it's a rather strange beast and it acts a bit differently from normal optional values. Roman Perepelitsa.