Convert Quarto document to R script — qmd_to_r

Extracts R code cells from a Quarto document and writes them to an R script file that can be rendered with the same options. The Markdown text is not preserved, but R chunk options are kept as comment headers using Quarto's #| syntax.

This function is still experimental and may slightly change in future releases, depending on feedback.

Usage

qmd_to_r_script(qmd, script = NULL)

Arguments

qmd: Character. Path to the input Quarto document (.qmd file).
script: Character. Path to the output R script file. If NULL (default), the script file will have the same name as the input file but with .R extension.

Value

Invisibly returns the path to the created R script file, or NULL if no R code cells were found.

Details

This function processes a Quarto document by:

Extracting only R code cells (markdown and cell in other languages are ignored)
Preserving chunk options as #| comment headers
Adding the document's YAML metadata as a spin-style header
Creating an R script that can be rendered with the same options

File handling:

If the output R script already exists, the function will abort with an error
Non-R code cells (e.g., Python, Julia, Observable JS) are ignored
If no R code cells are found, the function does nothing and returns NULL

Compatibility:

The resulting R script is compatible with Quarto's script rendering via knitr::spin() and can be rendered directly with quarto render script.R. See https://quarto.org/docs/computations/render-scripts.html#knitr for more details on rendering R scripts with Quarto.

The resulting R script uses Quarto's executable cell format with #| comments to preserve chunk options like echo, eval, output, etc.

Examples

if (FALSE) { # \dontrun{
# Convert a Quarto document to R script
qmd_to_r_script("my-document.qmd")
# Creates "my-document.R"

# Specify custom output file
qmd_to_r_script("my-document.qmd", script = "extracted-code.R")
} # }