Subject: [boost] boost::any_ref and boost::any_const_ref
From: Daniel Larimer (dlarimer_at_[hidden])
Date: 2010-02-14 14:23:11
I am attempting to create a library with a generic interface run-time interface and have need for something like boost::any; however, boost::any requires heap allocation. boost::variant is not acceptable either because I do not know the full set of types in advance.
Has anyone seen the equivalent of a type-checked void* or const void*?
Effectively I would like to create a polymorphic method like this:
void myclass::method( const_any_ref p1, const_any_ref p2, const any_ref p3 )
const uint16_t& _p1 = p1;
const double& _p2 = p2;
const std::string& _p3 = p3;
//If any of the types do not match it should throw an exception.
alternatively the follow syntax may work if you want to avoid exceptions?
boost::optional<const uint16_t&> _p1 = p1;
if( !_p1 ) // cast failed?
Anyone have any nifty ideas on how to accomplish this without RTTI and no heap allocation?
In place of RTTI I do have a "manual" RTTI system that I could use.
get_typename<T>::str will return a unique const char* pointer.
I am guessing the best I can hope for is a pair of pointers, one "void*" and one const char*.
I am going to write such a class unless someone here knows of an existing solution.
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