Add a Column Spanner to a Blueprint — add

Groups one or more columns under a shared header label. Spanners can reference other spanners by id to create nested hierarchies.

Usage

add_spanner(
  blueprint,
  label,
  columns = NULL,
  id = NULL,
  spanners = NULL,
  level = NULL
)

blueprint: A table1_blueprint object
label: Character string displayed as the spanner header
columns: Integer vector of column indices or character vector of column names to group under this spanner
id: Optional unique identifier for this spanner. Defaults to a sanitised version of label. Required when building nested spanners that reference this one as a parent.
spanners: Character vector of child spanner ids to nest under this spanner. When provided, columns is ignored and the spanner covers all columns owned by the referenced children.
level: Integer spanner level (1 = closest to data columns). Normally computed automatically; set manually only to force a specific position.

The blueprint, modified in place (spanner appended to blueprint$metadata$spanners).