title: Error installing Dart Development version on OS X with homebrew
body: <p>Have installed several versions of Dart on OS X using homebrew.</p>
  
  <pre><code>brew tap dart-lang/dart
  brew install dart
  </code></pre>
  
  <p>Today I did a 'brew upgrade' to Dart 1.11.3 stable, because I want to run cucumber/selenium/chromedriver tests in dartium. Dartium is still at version 39.* and chromedriver wants 40something.</p>
  
  <p><em>note: windows users are able to run these tests in dartium :(</em></p>
  
  <p>So, tried installing development version 1.12.0-dev.5.0 to see if dartium would also upgrade. No joy</p>
  
  <pre><code>brew install dart --devel
  
  Warning: dart-lang/dart/dart-1.11.3 already installed
  </code></pre>
  
  <p>Do I really have to uninstall to install the development version?</p>