pub fn kind_class(kind: ColumnKind) -> Option<&'static str>Expand description
The class saying what a column holds, or None for prose.
wiki table-model: the kind carries the look, so the class goes on every
cell and on the heading, and the sheet rules each kind once. Text is the
absence of a kind, as cell-keeps would be if a keep needed saying, so it
writes nothing. A kind added upstream reads as text: plain, never missing.