The type-system is supposed to be our friend, not our enemy. I pushed this without PR, because the buildbots don't build the templates by default. That requires configure -DENABLE_ROSAPPS=1 -DENABLE_ROSAPPS_TEMPLATES=1 So no gain in running them. Greta Thunberg will appreciate the saved CPU-cycles to fight global warming. I verified it locally to compile without warnings on GCC8.4.0dbg x86 and it follows the same pattern as 0.4.15-dev-6626-g 806da4421c13becf47735ad33f18dafd542497df which passed all the bots successfully. Also the x64 ones.