Deparse a table's column header back to editable rtf_col_header() source

Renders the current column header of a finished rtftable() (or the first page of an as_rtftables() list) as rtf_col_header(...) source text, addressed by column name, so you can copy it, edit the labels / spans, and re-apply with set_col_header(). It is the inverse companion of set_col_header() and pairs with rtf_columns() (which lists the final column names).

Usage

rtf_header_source(
  x,
  level = c("explicit", "default", "all"),
  snippet = TRUE,
  add_span_level = FALSE,
  stub = 1
)

Arguments

x

An rtftable(), or a list of them (pages from as_rtftables(); the first page is used).

level

Verbosity of the emitted cells: "explicit" (default – only fields that differ from the defaults), "default" (also show each cell's effective align and default border widths, but not the FALSE decoration flags), or "all" (everything, including bold = FALSE etc.).

snippet

Logical (default TRUE). When TRUE, wrap the header in a pipeable set_col_header(...) call that also reproduces the header text alignment (from col_spec) and the header-related zone borders (header / spanning, via style_zone()). There is no leading tbl |> – the first argument is meant to arrive through the pipe (e.g. my_tbl |> followed by the snippet). When FALSE, return the bare rtf_col_header(...) value.

add_span_level

Logical (default FALSE). When TRUE, prepend a scaffold spanning row grouping the non-stub columns (see Details).

stub

Column(s) to keep un-spanned when add_span_level = TRUE: integer position(s) and/or column name(s). Default 1 (the first column, where as_rtftables(stub = ) places the stub).

Value

A single character string (the source). Use cat() to print it with the line breaks rendered.

Details

The output is name-based (cell positions are written as column names, which survive reordering), keeps the header's empty gap cells, and backtick-quotes non-syntactic column names. Per-cell text decorations and borders are reproduced faithfully.

add_span_level = TRUE previews adding a second hierarchy level: the stub column(s) stay as single (empty) cells and every other column is bundled under one empty spanning cell whose label you fill in – a quick scaffold for turning a one-row header into a grouped, two-row header.

See also

set_col_header() to apply an edited header; rtf_columns() for the final column names; rtf_col_header() / col_cell() for the pieces.

Examples

tbl <- rtftable(
  data.frame(row_label = "x", g1 = 1, g2 = 2, Total = 3),
  col_header = c("Category", "Low", "High", "Total")
)
cat(rtf_header_source(tbl, snippet = FALSE))
#> rtf_col_header(
#>     c(row_label = "Category", g1 = "Low", g2 = "High", Total = "Total")
#>   )

# Preview adding a spanning level over the non-stub columns:
cat(rtf_header_source(tbl, snippet = FALSE, add_span_level = TRUE))
#> rtf_col_header(
#>     list(col_cell("row_label", ""), col_cell(c("g1", "Total"), "")),
#>     c(row_label = "Category", g1 = "Low", g2 = "High", Total = "Total")
#>   )