Document abstract and concrete operator helpers
Document abstract and concrete operator helpers

smharper/openmc,amandalund/openmc,liangjg/openmc,liangjg/openmc,amandalund/openmc,walshjon/openmc,paulromano/openmc,smharper/openmc,smharper/openmc,liangjg/openmc,shikhar413/openmc,walshjon/openmc,shikhar413/openmc,shikhar413/openmc,walshjon/openmc,walshjon/openmc,paulromano/openmc,paulromano/openmc,mit-crpg/openmc,amandalund/openmc,mit-crpg/openmc,smharper/openmc,mit-crpg/openmc,liangjg/openmc,paulromano/openmc,shikhar413/openmc,amandalund/openmc,mit-crpg/openmc