title: why does kable not print when used within a function in rmarkdown
body: <p>I have to repeat certain outputs in many rmarkdown reports and want to write a function to use for this.</p>
  
  <p>Calling a function outputs plots ok when I knit the rmd file but not kable data frames.</p>
  
  <p>For example</p>
  
  <pre><code>---
  title: "Markdown example"
  output: html_document
  ---
  
  ```{r setup, include=FALSE}
  knitr::opts_chunk$set(echo = TRUE)
  ```
  
  # Markdown example
  ```{r mtcars}
  make_outputs &lt;- function(){
    knitr::kable(head(mtcars))
    plot(mtcars$mpg, mtcars$cyl)
    hist(mtcars$cyl)
  }
  
  make_outputs()
  
  ```
  </code></pre>
  
  <p>Displays the plots but not the kable table.</p>