title: why Golang handle cutoff in atoi.go like this?
body: <pre><code>// code in atoi.go, line 90
  var cutoff uint64
  switch base {
  case 10:
      cutoff = maxUint64/10 + 1
  case 16:
      cutoff = maxUint64/16 + 1
  default:
      cutoff = maxUint64/uint64(base) + 1
  }
  </code></pre>
  <p>I saw some code in file atoi.go of Golang package, why not write it like below?</p>
  <pre><code>var cutoff = maxUint64/uint64(base) + 1
  </code></pre>
  <p>Thanks a lot.</p>