GRID_ATTR_UNDERSCORE
(attr & GRID_ATTR_UNDERSCORE) ? "underscore," : "",
{ "underscore", GRID_ATTR_UNDERSCORE },
{ GRID_ATTR_UNDERSCORE, 4 },
gc->attr |= GRID_ATTR_UNDERSCORE;
gc->attr |= GRID_ATTR_UNDERSCORE;
(GRID_ATTR_UNDERSCORE| \
if (changed & GRID_ATTR_UNDERSCORE)