Used in _if functions to enable type-based selection even when the data
is lazily generated. Should either return the complete tibble, or if that
can not be computed quickly, a 0-row tibble where the columns are of
the correct type.
Used in _if functions to enable type-based selection even when the data
is lazily generated. Should either return the complete tibble, or if that
can not be computed quickly, a 0-row tibble where the columns are of
the correct type.