Read an ARD table definition from a workbook

Usage

tfl_read_table_spec(path, output_id = NULL)

path: An .xlsx workbook (needs readxl) with the sheets of tfl_table_spec() (study, tables, variables, cells, layout, columns, style, col_header). Any of them may be absent. A definition is one file with several sheets, so it is an Excel workbook and nothing else.
output_id: The report to narrow the workbook to. Rows with a blank output_id are the study's defaults and stay; a row naming this report replaces the default with the same key. NULL (default) reads the whole workbook; what needs one report — rtfreporter::table_plan(), tfl_report() — then takes a workbook of one report as it is and asks which of several.

The ARD functions and the plan are rtfreporter's: help("ard-tables", package = "rtfreporter").