Currently, boost::any supports two kinds of conversion: 1. Unchecked conversion to pointer (NULL is returned if conversion is impossible) 2. Checked conversion to value type (exception is thrown if conversion is impossible) I'd like to have another variant -- checked conversion to reference. The following code does not compile: boost::any a = 1; int& i = boost::any_cast<int&>(a); There are two issues: 1. Documentation says: If passed a value or reference, it returns a copy of the value content if successful. But even if I change the above to boost::any a = 1; int i = boost::any_cast<int&>(a); it does not compile. Docs are at least inaccurate. 2. Can we make the above work? I attach a patch which implements casting to reference, and passes all the existing test. I'd like this behaviour because currently program_options contains code such as: template<class T> T& variable_value::as() { T* r = boost::any_cast<T>(&v); if (!r) throw boost::bad_any_cast(); return *r; } which is plain ugly. With the patch, the above can be written as template<class T> T& variable_value::as() { return boost::any_cast<T&>(v); } - Volodya