for (int vi = 0; vi < groupdata.numvars; ++vi)

        for (int vi = 0; vi < groupdata.numvars; ++vi) {

            CCTK_VERROR(
                "MakeNewLevelFromCoarse before prolongation: Grid function "
                "\"%s\" is invalid on refinement level %d, time "
                "level %d; expected valid %s, found valid %s",
                CCTK_FullVarName(coarsegroupdata.firstvarindex + vi),
                coarseleveldata.level, tl, string(all_valid).c_str(),
                string(coarsegroupdata.valid.at(tl).at(vi)).c_str());

            CCTK_VERROR("MakeNewLevelFromCoarse before prolongation: Grid "
                        "function \"%s\" is invalid on refinement level %d, "
                        "time level %d; expected valid %s, found valid %s",
                        CCTK_FullVarName(coarsegroupdata.firstvarindex + vi),
                        coarseleveldata.level, tl, string(all_valid).c_str(),
                        string(coarsegroupdata.valid.at(tl).at(vi)).c_str());

        }