private static void Main(string[] args)
{
/* The forum and its posts and their posts and so on is our syntax tree.
* Syntax tree consists of expressions which are used to interpret data in certain context.
* Forum and Post are all implementing the IExpression.
* Context is the context at which each expression is interpreted.
* Its depth property is needed for the proper interpretation of each post node.
* The interpreted result is also saved in the output property of context.
* Here the syntax tree is constructed manually by the client.
* In real world it is constructed with the help of a parser.
*/
var forum = new Forum();
var post1 = new Post("Post 1 message.");
var post11 = new Post("Post 1 reply 1 message");
var post12 = new Post("Post 1 reply 2 message");
var post121 = new Post("Post 1 reply 2 repy 1 message");
post12.AddReply(post121);
post1.AddReply(post11);
post1.AddReply(post12);
forum.AddPost(post1);
var post2 = new Post("Post 2 message.");
var post21 = new Post("Post 2 reply 1 message.");
post2.AddReply(post21);
forum.AddPost(post2);
var ctx = new Context();
forum.Interpret(ctx);
Console.WriteLine(ctx.Output);
}
public void Interpret(Context ctx)
{
ctx.Output = "<--Forum start-->\n";
foreach (var post in this.posts)
{
post.Interpret(ctx);
}
ctx.Output += "<--Forum end-->";
}
public void Interpret(Context ctx)
{
ctx.Output += this.Msg + "\n";
ctx.Depth++;
foreach (var post in posts)
{
ctx.Output += new String(' ', ctx.Depth * 4);
post.Interpret(ctx);
}
ctx.Depth--;
}
public static void Main(string[] args)
{
Context context = new Context();
ArrayList list = new ArrayList();
list.Add(new TerminalExpression());
list.Add(new NonTerminalExpression());
list.Add(new TerminalExpression());
list.Add(new TerminalExpression());
foreach(AbstractExpression exp in list)
{
exp.Interpret(context);
}
Console.ReadLine();
}
