fn for info_snippet(): get a list of column categoriesThe snip_list() function can be used as an info_snippet() function (i.e.,
provided to fn) to get a catalog list from a table column. You can limit
the of items in that list with the limit value.
snip_list(column, limit = 5)The name of the column that contains the target values.
A limit of items put into the generated list. The returned text
will state the remaining number of items beyond the limit.
A formula needed for info_snippet()'s fn argument.