Adds a header row to the global TFL options, which can be used as defaults for all spec objects.
Usage
# S3 method for class 'TFL_options'
add_header(spec, ..., level = NULL)Arguments
- spec
TFL_options object
- ...
Up to 3 character strings (left, center, right)
Positional parts represent left, center and right header/footer cells respectively.
Supply fewer than 3 parts if some cells should be empty; use empty string "" for explicit empties.
Each call appends one header/footer row; use the
levelparameter to replace an existing row.
- level
Optional numeric index. If provided, replaces header at that row. If NULL, appends next row.