[r] How to add \newpage in Rmarkdown in a smart way?

I wonder if one could simply use LaTeX \newpage command in R markdown v2 in a different way than this:

```{r, results='asis', echo=FALSE}
cat("\\newpage")
```

I produce pdf_output. If any1 has any idea please do not hesitate to comment :) ! Thanks

I create pdf like this:

---
title: " "
author: " "
date: "2014"
output: 
   pdf_document:
      includes:
         in_header: naglowek.tex
      highlight: pygments
      toc: true
      toc_depth: 3
      number_sections: true
      keep_tex: true
---

In the initialization chunk I define a function

pagebreak <- function() {
  if(knitr::is_latex_output())
    return("\\newpage")
  else
    return('<div style="page-break-before: always;" />')
}

In the markdown part where I want to insert a page break, I type

`r pagebreak()`

You can make the pagebreak conditional on knitting to PDF. This worked for me.

```{r, results='asis', eval=(opts_knit$get('rmarkdown.pandoc.to') == 'latex')}
cat('\\pagebreak')
```