Hash an arbitrary precision value (boost::multiprecision::cpp_int)

Question

I need to get the hash of value with arbitrary precision (from Boost.Multiprecision); I use the cpp_int backend. For now, I came up with the following code:

Answer 1

Just to say that I've just added native hashing support (for Boost.Hash and std::hash) to git develop. It works for all the number types including those from GMP etc. Unfortunately that code won't be released until Boost-1.62 now.

The answer above that (ab)uses serialization support, is actually extremely cool and really rather clever ;) However, it wouldn't work if you wanted to use a vector-based hasher like CityHash, I added an example of using that by accessing the limbs directly to the docs: https://htmlpreview.github.io/?https://github.com/boostorg/multiprecision/blob/develop/doc/html/boost_multiprecision/tut/hash.html Either direct limb-access or the serialization tip will work with all previous releases of course.