title: How to write elisp to auto-correct misspelt variables
body: <p>Suppose I wrote</p>
  
  <pre><code>var longlongname = 1;
  </code></pre>
  
  <p>and I misspelled it as <strong>linglongname</strong>. How can I find a package or write a function to correct it?</p>
  
  <p>(sometimes I'm lazy and prefer to trigger a key to fix previous misspelt word rather than move cursor around and correct it manually.)</p>