Extract only text from Rmd documents

Question

Not even sure if this is possible, but is there a way to extract only the raw text portion of the .Rmd file and discard any code? Or basically converting an .Rmd file into .txt file within R?

I've tried the function readLines, but this makes a huuuuuge character with all kinds of (to me) useless meta-data.

Answer 1

You can knit document without evaluating and including code.

Here's an example of dummy document foo.Rmd:

# Header 1

foo

## Header 2

bar

## Header 22

foobar

```{r}
1
```

text text text

```{r}
print(2)
```

We can knit this document using knitr::knit("foo.Rmd"), but in this case code chunks will be included in text. To deal with this we need to set knitr options:

library(knitr)
opts_chunk$set(list(echo = FALSE, eval = FALSE))
knit("foo.Rmd")

This command will create output document foo.md only with text.