title: How use and run Swift 2.3 on command line
body: <p>How do you start Swift on the command line? And how do you compile files on the command line with Swift 2.3? Since I updated to Xcode 8 I get Swift 3 by default.</p>
  
  <pre><code>$ xcrun swift
  Welcome to Apple Swift version 3.0 (swiftlang-800.0.46.2 clang-800.0.38). Type :help for assistance.
  </code></pre>