title: Creating custom spell checking for html
body: <p>Is it possible to use some custom functions for spell checking in html inputs? For example I have an input where values are divided by spaces (or commas, doesn't matter) and a function which receives tokens from it. That function decides if token is spelled correctly (in my case there would be some regular expression) and returns true/false value and based on that some words would be underlined. In my head it looks something like this:</p>
  <pre><code>&lt;input type=&quot;text&quot; onCheck=&quot;checkToken&quot;&gt;
  
  &lt;script&gt;
  function checkToken(token) {
    const oneCrazyRegex = /[a-b]/;
    return oneCrazyRegex.test(token);
  &lt;/script&gt;
  </code></pre>
  <p>Or taking whole input:</p>
  <pre><code>function spellCheckInput(line) {
    // line is an array of tokens
    return line.map(tok =&gt; checkToken(tok));
  }
  </code></pre>
  <p>Is it possible to do with js/css/html or not?</p>
  <p>P.S. <code>onCheck</code> is example only, I know that this attribute is not valid</p>