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Boost Exception


#include <boost/exception/enable_current_exception.hpp>

    template <class T>
    ---unspecified--- enable_current_exception( T const & e );


  • T must be a class with an accessible no-throw copy constructor.
  • If T has any virtual base types, those types must have an accessible default constructor.


An object of unspecified type which derives publicly from T. That is, the returned object can be intercepted by a catch(T &).


This function is designed to be used directly in a throw-expression to enable the exception_ptr support in Boost Exception. For example:

    public std::exception

throw boost::enable_current_exception(my_exception());

Unless enable_current_exception is called at the time an exception object is used in a throw-expression, an attempt to copy it using current_exception may return an exception_ptr which refers to an instance of unknown_exception. See current_exception for details.


Instead of using the throw keyword directly, it is preferable to call boost::throw_exception. This is guaranteed to throw an exception that derives from boost::exception and supports the exception_ptr functionality.