How to display verbatim inline r code with backticks using Rmarkdown?

Question

By doubling the backticks in Markdown, it is easy to render some text in code style including the backticks, such as: `r 2+2`. But how to do that with RMarkdown ? By the same way we can display `t 2+2`, but replacing t with r executes the R code 2+2.

The only way I have found so far is:

<p><code  class="r">`</code><code class="r">r 2+2`</code></p> 

Not very convenient. Maybe I should define a new css for doing that more conveniently ?

Answer 1

Here is a trick that I use. First, note \x60 is `:

> cat('\x60', '\n') `  

Then you write

`r '\x60r foo+bar\x60'` 

which will give you `r foo+bar` in the markdown output, but that will become r foo+bar in the HTML output, so you need to protect the backticks in markdown, using two (or more) backticks. Then you end up with this hairball:

`` `r '\x60r foo+bar\x60'` `` 

Your own solution is good, but I'd just define

rinline <- function(code) {   sprintf('``` `r %s` ```', code) } 

Also see this post for another trick.

Answer 2

To anyone looking at this now, you may want to check out the more recent solution here: embed Rmarkdown without knitr evaluation

Essentially you can do:

Some R code inline : `r knitr::inline_expr("2+2")` 

I'm guessing that the functionality describe above has been added to knitr directly but it saves us defining the function ourselves.