C++ 128/256-bit fixed size integer types

Question

I was wondering if any fellow SO\'s could recommend a good light-weight fixed size integer type (128-bit or even 256-bit, possibly even template parametrized) library.

Answer 1

Depending on your requirements, the STL class bitset might fit your needs. It responds to all the bit-manipulation operators that integer types do (<<,| etc.), but unfortunately not to arithmetic operators like + or *. Its size is fixed at compile time via a template parameter. Another unfortunate thing is that the API provides no way to get at the underlying binary representation (e.g. for streaming it), which might seriously limit its usefulness.

(I know this is an old question, but this answer might help others.)