title: ANTLR grammar is giving unexpected results
body: <p>This is very simple.  I'm in the process of learning ANTLR4 by inventing a grammar that can recognize a single word.  But why isn't it matching my name?  It's printing out <code>[ ]</code>.</p>
  
  <p>I am using Antlr 4 with C# 4.5.</p>
  
  <h3>MyFirstGrammar.g4:</h3>
  
  <pre><code>grammar MyFirstGrammar;
  
  /*
   * Parser Rules
   */
  
  compileUnit
      :   ID
      ;
  
  
  /*
   * Lexer Rules
   */
  
  ID  :   [A-Za-z]+ ;
  
  WS  :   ' ' -&gt; skip ;
  </code></pre>
  
  <h3>Program.cs</h3>
  
  <pre><code>static class Program
  {
      private static void Main()
      {
          var stream = new AntlrInputStream("amy");
          var lexer = new Grammars.MyFirstGrammarLexer(stream);
          var tokens= new CommonTokenStream(lexer);
          var parser = new Grammars.MyFirstGrammarParser(tokens);
          var root = parser.compileUnit();
          Debug.WriteLine(root);
      }
  }
  </code></pre>