title: Regex pattern to produce appropriate escape character behavior
body: <p>I'm making a Sublime Text 3 language definition for syntax highlighting. The language is a simple 'expression language' (nothing to do with Java) that is used to display information from a media library on a display panel. The purpose of the syntax highlighting is to clarify exactly what will be displayed on the panel.</p>
  
  <p>Accordingly, I would like to explicate exactly what a sequence of escape characters will look like when interpreted and shown on the display panel. The escape character is a forward-slash, and if you would like to display a literal forward-slash, you have to escape it with another. Therefore, a series of forward-slashes will result in every-other forward-slash being displayed on the panel. Additionally, if there is a special character after a forward-slash, it will be escaped - but if a special character is placed after TWO (or four, or six...) forward slashes, it will not be escaped, because the escape characters will cancel each other out.</p>
  
  <p>The highlighting I would like to achieve (with example special character 's') is as follows:</p>
  
  <p><a href="https://i.stack.imgur.com/L0sWK.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/L0sWK.png" alt="Desired Highlighting"></a></p>
  
  <p>I have to achieve this simply by feeding Sublime Text regular expressions, in YAML format, so the solution has to be one made purely of regex.</p>
  
  <p>Is this possible? If so, how can I achieve it?</p>