Add spin preamble to R script — add_spin

Adds a minimal spin preamble to an R script file if one doesn't already exist. The preamble includes a title derived from the filename and is formatted as a YAML block suitable preprended with #' for knitr::spin().

Usage

add_spin_preamble(script, title = NULL, preamble = NULL)

Arguments

script: Path to the R script file
title: Custom title for the preamble. If provided, overrides any title in the preamble list. If NULL, uses preamble$title or filename as fallback.
preamble: Named list of YAML metadata to include in preamble. The title parameter takes precedence over preamble$title if both are provided.

Value

Invisibly returns the script path if modified, otherwise invisible NULL

Details

This is useful to prepare R scripts for use with Quarto Script rendering support. See https://quarto.org/docs/computations/render-scripts.html#knitr

Preamble format

For a script named analysis.R, the function adds this preamble by default:

#' ---
#' title: analysis
#' ---
#'

# Original script content starts here

This is the minimal preamble required for Quarto Script rendering, so that Engine Bindings works.

Examples

if (FALSE) { # \dontrun{
# Basic usage with default title
add_spin_preamble("analysis.R")

# Custom title
add_spin_preamble("analysis.R", title = "My Analysis")

# Custom preamble with multiple fields
add_spin_preamble("analysis.R", preamble = list(
  title = "Advanced Analysis",
  author = "John Doe",
  date = Sys.Date(),
  format = "html"
))

# Title parameter overrides preamble title
add_spin_preamble("analysis.R",
  title = "Final Title",  # This takes precedence
  preamble = list(
    title = "Ignored Title",
    author = "John Doe"
  )
)
} # }