Concatenate a Value to Cell Text in Conditional Rows

Declares a glue action to concatenate a value — from a data column or a literal string — to the display text of specified cells in rows matching the parent compute_cols() condition.

Usage

c_glue(cols, position, glue_col = NULL, text = NULL, separator = NULL)

Arguments

cols: Tidyselect expression for the target columns (e.g., col1, c(col1, col2), starts_with("x")). Must resolve to visible (non-hidden) report columns only.
position: Character. Concatenation side: "before" prepends the glue value to the existing cell text; "after" appends it.
glue_col: Optional. Unquoted column name whose formatted value is concatenated onto the target cells. The column may be hidden (not in the visible column list). Mutually exclusive with text.
text: Optional. A single literal character string to concatenate onto the target cells. Mutually exclusive with glue_col.
separator: Character string inserted between the existing cell text and the glued value when both sides are non-empty. Defaults to "" (direct concatenation). When either side is empty, no separator is inserted.

Value

Quosure-style marker (internal use within compute_cols())

Details

Must be called inside compute_cols().

Constraints:

Exactly one of glue_col or text must be provided.
cols resolves only visible report columns via tidyselect.
glue_col can reference any data column, including hidden ones.
glue_col must not overlap with cols.

Behavior:

When the glue value (from glue_col or text) is empty or NA, the action is silently skipped for that row/cell.
When a target cell was suppressed by deduplication (dedupe = TRUE on that column), the glue is silently skipped to preserve the visual suppression of repeated values.
When a target cell is suppressed by a concurrent c_merge() action (i.e., it is a non-leader merged cell), the glue is silently skipped.
The merge leader cell is glued normally when c_glue() targets a column involved in c_merge() as the first column.
Multiple c_glue() calls on the same column accumulate in call order.

Interaction with other actions:

c_style(): Fully compatible — styling and text modification are independent.
c_merge(): Compatible. Glue is processed after merge in the renderer. Non-leader (suppressed) merge cells are skipped; the merge-leader cell is glued normally.
c_addrow(): Stackable — when used together in the same compute_cols(), c_addrow() sees glued values. This allows building compound cell values (e.g., "PARAM: VISIT") before using them in inserted rows.
c_pageBreak(): Fully compatible.

Stackable Actions: Actions within a single compute_cols() call execute sequentially in the order specified. This means c_glue() modifications are visible to subsequent c_addrow() actions in the same call, enabling complex multi-step transformations.

Examples

if (FALSE) { # \dontrun{
  # Append a unit from a hidden column (e.g. unit_col is not in spec cols)
  spec <- compute_cols(spec, !is.na(value),
    c_glue(value, "after", glue_col = unit, separator = " "))

  # Prepend a literal marker to a label column
  spec <- compute_cols(spec, is_total,
    c_glue(label, "before", text = ">> "))

  # Combine with c_style() — independent operations
  spec <- compute_cols(spec, firstOf(group),
    c_glue(label, "before", text = "> "),
    c_style(label, styleRef = "bold"))
  
  # Stackable with c_addrow() — addrow sees glued values
  spec <- compute_cols(spec, PARAM == "ALT",
    c_glue(PARAM, "after", glue_col = VISIT, separator = ": "),
    c_addrow("above", value_from = PARAM)  # Uses "ALT: Week 2"
  )
} # }