title: Scala split a multi line string by lines that contain all hyphens
body: <p>I have a multiline string that contains:</p>
  
  <pre><code>this is line 1
  
  ------------------------------
  
  this is line 2
  
  +++++++++++++++++++++++++
  
  this is line 3 
  
  ---------------
  
  this is line 4
  </code></pre>
  
  <p>I want to divide this string into chunks by splitting on lines that contains only (-,+), I tried regular expression (^++$)|(^-+$) that worked fine on regex validators, but it's not working in Scala.</p>