title: How to undo "go mod init"
body: <p>The version of Go I'm using is</p>
  <pre><code>go version
  go version go1.15.6 darwin/amd64
  </code></pre>
  <p>I did <code>go mod init example.com/m</code> under my folder <code>/***.com/m/</code>
  Now I would like to do <code>go mod init ***.com/m</code>, it shows as</p>
  <pre><code>go.mod already exists
  </code></pre>
  <p>How could I clean up the <code>go.mod</code> which is unwanted?</p>