Interpreter Design Pattern in C#

Given a language, defines a representation for its grammar along with an interpreter that uses the representation to interpret sentences in the language.

This structural code demonstrates the Interpreter patterns, which using a defined grammer, provides the interpreter that processes parsed statements.

using System;
using System.Collections;

  class MainApp
  {
    static void Main()
    {
      Context context = new Context();

      // Usually a tree 
      ArrayList list = new ArrayList(); 

      // Populate 'abstract syntax tree' 
      list.Add(new TerminalExpression());
      list.Add(new NonterminalExpression());
      list.Add(new TerminalExpression());
      list.Add(new TerminalExpression());

      // Interpret 
      foreach (AbstractExpression exp in list)
      {
        exp.Interpret(context);
      }

      // Wait for user 
      Console.Read();
    }
  }

  // "Context" 
  class Context 
  {
  }

  // "AbstractExpression" 
  abstract class AbstractExpression 
  {
    public abstract void Interpret(Context context);
  }

  // "TerminalExpression" 
  class TerminalExpression : AbstractExpression
  {
    public override void Interpret(Context context)  
    {
      Console.WriteLine("Called Terminal.Interpret()");
    }
  }

  // "NonterminalExpression" 
  class NonterminalExpression : AbstractExpression
  {
    public override void Interpret(Context context)  
    {
      Console.WriteLine("Called Nonterminal.Interpret()");
    }  
  }