Create RMarkdown headers and code chunks in purrr

[dylanrussellmd]

The following .Rmd is what I think should produce what I'm looking for:

---
title: "Untitled"
date: "10/9/2021"
output: html_document
---

```{r setup, include=FALSE}
knitr::opts_chunk$set(echo = FALSE)

full_var <- function(var) {
  cat("### `", var, "` {-} \n")
  cat("```{r}", "\n")
  cat("print('test')", "\n")
  cat("```", "\n")
}

vars <- c("1", "2", "3")
```

```{r results = "asis"}
purrr::walk(vars, full_var)
```

Instead, it looks like:

Why is the print('test') not being evaluated and instead being presented as a code block?

[Equation]

In your "code execution" line, use cat(eval()):

---
title: "Untitled"
date: "10/9/2021"
output: html_document
---

```{r setup, include=FALSE}
knitr::opts_chunk$set(echo = FALSE)

full_var <- function(var) {
  cat("### ",  var, "{-}", "\n")
  cat("```{r}", "\n")
  cat(eval(print('test')), "\n")
  cat("```", "\n")
}

vars <- c("1", "2", "3")

purrr::walk(vars, full_var)

Notice that I also changed the heading line slightly.

[dylanrussellmd]

Thanks! I thought the answer to this would help me solve my problem, but apparently not:

Consider if print('test') was actually a much lengthier chunk of Markdown and code block and so I wrote it in a separate .Rmd file.

full_var <- function(var) {
  cat("### ",  var, "{-}", "\n")
  cat("```{r child = '", var, ".Rmd'}", "\n", sep = "")
  cat("```", "\n")
}

This simply returns {r child = 'var.Rmd'} but does not actually pull in the Markdown from the other file. Any idea why this may not be working?

[Equation]

Make use of the knitr::knit_child() call in your function:

---
title: "Untitled"
date: "10/9/2021"
output: html_document
---

```{r setup, include=FALSE}
knitr::opts_chunk$set(echo = FALSE)

full_var <- function(var) {
  cat("### ",  var, "{-}", "\n")
  cat("\n")
  
  child <- knitr::knit_child(paste0(var, ".Rmd"), quiet = TRUE)
  
  cat(child, sep = "\n")
 
}

vars <- c("1", "2", "3")
```

```{r results = "asis"}
purrr::walk(vars, full_var)
```

This should read your child .Rmd files, provided, of course, that they are located in your working directory.

[dylanrussellmd]

Thank you! I've been beating my head against a wall trying to get this to work - it was so simple the whole time.

[cderv]

Yes knit_child() is a good solution.

If you want to go further, have a look in the R Markdown cookbook. There are seveal chapter with recipes to help with such task.

11.11 Output text as raw Markdown content (*) | R Markdown Cookbook

14.7 Use knitr::knit_expand() to generate Rmd source | R Markdown Cookbook

16.4 Child documents (*) | R Markdown Cookbook

Hope it helps