How to generate full qmd file from child files? - r-markdown

Question

I have a quarto file with several child documents. I can render them just fine.
But I would like to generate a single qmd file that contains the full document.
So basically I need some kind of qmd to qmd converter. Is there a way to do that?
Sections like this insert the children:
```{r}
#| label = "child1",
#| eval = TRUE,
#| child = "child1.qmd"
```

Answer 1

Seems noone has a "nice" solution. So here is a hack to put things together "manually".
It finds the code blocks with a child defined and replaces that code box with the text from the references child.
merge_children <- function(file, path_prefix, outpath, child_pattern = "[[:blank:]]*#\\|[[:blank:]]*child[[:blank:]]*=.*,+[[:blank:]]*", child_capture = "[[:blank:]]*#\\|[[:blank:]]*child.*=.*,+[[:blank:]]*"){
# read file
txt <- readLines(file)
# find children
child_defs <- txt %>% grep(child_pattern,.)
# find children paths
child_paths <- map_chr(child_defs, function(x){
txt[x] %>%
gsub(child_capture,"\\1", .) %>%
gsub('.*\\"(.*)\\".*',"\\1", .)
}
)
if(length(child_paths)==0){
writeLines(txt, outpath)
return(message("No children found. Will just copy file."))
}
child_paths <- paste0(path_prefix, child_paths)
#find start and end of relevant code sections
code_start <- txt %>% grep("^[[:blank:]]*```\\{r.*",.)
code_end <- txt %>% grep("^[[:blank:]]*```[[:blank:]]*$",.)
# read children
txt_children <- map(child_paths, readLines)
indeces <- sort(c(1, code_start, code_end+1))
txt_split <- split(txt, rep(seq(indeces), diff(c(indeces, length(txt)+1))))
has_child <- map_lgl(txt_split, ~any(grepl(child_pattern,..1))) %>% as.vector %>% which
# replace children
if(length(has_child) != length(txt_children)) stop("children replacement indeces not equal to amount of children")
txt_split[has_child] <- txt_children
# put back together
txt_new <- txt_split %>% unlist()
writeLines(txt_new, outpath)
}