RegDomR
Do not use this gem, the cext is failing too often.
Instead use my pure ruby implementation ryodo (it's fast enough; a cext version is planned as well)
If you install it, though
… then it will install ryodo instead.
This gem behaves as a wrapper now.
If you use RegDomR module, you will actually use Ryodo.
require "regdomr"
RegDomR
#=> Ryodo
So, you really should switch to ryodo.