 for short rules.)
    Note, however, the <code>local</code> prefix in front of variables, which is needed
    so-as not to affect Lua&rsquo;s global environment. All in all, this is a minimal,
    working lexer that you can build on.</p>

    <p><a id="lexer.Tokens"></a></p>

    <h4>Tokens</h4>

    <p>Take a moment to think about your programming language&rsquo;s structure. What kind
    of key elements does it have? In the template shown earlier, one predefined
    element all languages have is whitespa