如何在knitr :: spin中输出文字反引号

Question

I'm trying to create some snippet templates for knitr::spin documents in R Studio, and I need them to include literal backticks so that the resulting document contains an R snippet:

Example of desired output:

#' ---
#' author: 'ENTER'
#' title: 'ENTER'
#' date: '`r Sys.time()`'
#' output: 
#'    html_document
#' ---

However, I can't figure out how to output backticks. This:

`r paste("#' date: '`Sys.time()`')`

will not work as the tick marks interrupt the paste command when rendering from R Studio snippet to R code. I've been trying to hash out the tick marks, adding forwards and backwards slashes etc., but haven't found a solution that renders this line correctly to:

#' date: '`r Sys.time()`'

---

Windows 7 Enterprise, 64-bit Operating System
R Version: 3.2.5
R Studio Version: 0.99.903
knitr Version: 1.14

---

Example: I tried this, but it still translates the R code instead of just printing the text:

snippet spin.header
`r paste("#' ---")`
`r paste("#' author: 'ENTER'")`
`r paste("#' title: 'ENTER'")`
`r paste("#' date:  '<code>``` `r Sys.time()` ```</code>'")`
`r paste("#' output:")` 
`r paste("#'    html_document")`
`r paste("#' ---")`

Answer 1

The correct answer was posted by rawr in the comments (he only missed r and a tick mark):

snippet spin.header
`r paste("#' ---")`
`r paste("#' author: 'ENTER'")`
`r paste("#' title: 'ENTER'")`
`r paste("#\' date: '\x60r Sys.time()\x60'")`
`r paste("#' output:")` 
`r paste("#'    html_document")`
`r paste("#' ---")`

Answer 2

One option is to break the token used during snippet processing for inline R.

snippet sh
  #' ---
  #' author: '${1:AUTHOR}'
  #' title: '${2:TITLE}'
  #' date: '`${3:}r Sys.time()`'
  #' output:
  #'    html_document
  #' ---
  ${0}

---

Another option is to avoid the inline R parsing completely.

snippet sh
  `r paste0(readLines("~/.R/snippets/spinheader.txt"),collapse = '\n')`

spinheader.txt

#' ---
#' author: '${1:AUTHOR}'
#' title: '${2:TITLE}'
#' date: '`r Sys.time()`'
#' output:
#'    html_document
#' ---
${0}