Extract R code from a Quarto document

qmd_to_r() extracts R code chunks from a .qmd file and writes them to a standalone .R script using knitr::purl(). It works on any .qmd file regardless of whether it was created with create_qmd().

Usage

qmd_to_r(input, output = NULL, documentation = 1L, quiet = TRUE)

Arguments

input

A character string with the path to the .qmd file.

output

A character string with the path to the output .R file. If NULL (the default), the output file is written to the same directory as input with the .qmd extension replaced by .R.

documentation

An integer controlling how much documentation is included in the extracted script. Passed to knitr::purl(): 0 strips all documentation; 1 (the default) includes chunk labels as comments; 2 includes full roxygen blocks.

quiet

Logical. If TRUE (the default), suppresses knitr's own output. toolero provides its own cli feedback instead.

Value

Invisibly returns the path to the output .R file.

Details

The parent directory of output is created if it does not already exist, and the creation is reported. knitr::purl() does not do this itself, so writing a derived script into R/ from a project that was not created by init_project() would otherwise fail.

Examples

# \donttest{
# Extract R code from a qmd file
qmd <- tempfile(fileext = ".qmd")
writeLines(c(
  "---",
  "title: Analysis",
  "---",
  "",
  "```{r}",
  "x <- 1 + 1",
  "```"
), qmd)

# Default output path: same directory, .R extension
qmd_to_r(input = qmd)
#> ✔ Extracted R code from /tmp/RtmpLziJOC/file1af613f6bb3b.qmd to /tmp/RtmpLziJOC/file1af613f6bb3b.R.

# Explicit output path. R/ is where toolero expects derived scripts;
# the directory is created if it does not exist yet.
out <- tempfile(fileext = ".R")
qmd_to_r(input = qmd, output = out)
#> ✔ Extracted R code from /tmp/RtmpLziJOC/file1af613f6bb3b.qmd to /tmp/RtmpLziJOC/file1af66cdba3f.R.

# Strip all documentation
qmd_to_r(input = qmd, output = out, documentation = 0L)
#> ✔ Extracted R code from /tmp/RtmpLziJOC/file1af613f6bb3b.qmd to /tmp/RtmpLziJOC/file1af66cdba3f.R.
# }