Currently this library provides some types for RPM NVRs: NV, NVR, NVRA, VerRel with read and display functions. There is also an ordering of VerRel based on rpm's vercmp which is implemented as rpmVerCompare.
See the haddock documentation for more details.
rpm-nvr is distributed under the GPLv2+ license.
The testsuite includes testcases for comparing rpm versions from the main rpm project.