A data frame of tt's cell values (processed by
value_fun, with columns named by the full column paths (processed by
path_fun and an additional row_path column with the row paths
(processed by by path_fun).
Arguments
tt
TableTree (or related class). A TableTree object representing a
populated table.
path_fun
function. Function to transform paths into single-string
row/column names.
value_fun
function. Function to transform cell values into cells of
the data.frame. Defaults to collapse_values which creates strings
where multi-valued cells are collapsed together, separated by |.