Robot Pattern)

 

Namespace Designpattern. Interpreter
{
Public   Abstract   Class Expression
{
Public Abstract BoolInterpret ();
}  
 
Public   Class Constant: Expression
{
Private   Bool M_val;
 
Public Constant ( Bool Val)
{
This. M_val=Val;
}  
 
Public   Override   Bool Interpret ()
{
Return This. M_val;
}  
 
Public   Override   String Tostring ()
{
Return This. M_val.tostring ();
}  
}  
 
Public   Class And: Expression
{
Public Expression left, right;

Public And (expression left, expression right)
{
This. Left=Left;
This. Right=Right;
}  
 
Public   Override   Bool Interpret ()
{
ReturnLeft. interpret ()&&Right. interpret ();
}  
 
Public   Override   String Tostring ()
{
Return   " ( " + This . Left. tostring () + " && " + This . Right. tostring () + " ) " ;
}  
}  
 
Public   Class Or: Expression
{
Public Expression left, right;

Public Or (expression left, expression right)
{
This. Left=Left;
This. Right=Right;
}  
 
Public   Override   Bool Interpret ()
{
ReturnLeft. interpret ()|Right. interpret ();
}  
 
Public   Override   String Tostring ()
{
Return   " ( " + This . Left. tostring () + " | " + This . Right. tostring () + " ) " ;
}  
}  
 
Public   Class Not: Expression
{
Private Expression exp;
 
Public Not (expression exp)
{
This. Exp=Exp;
}  
 
Public   Override   Bool Interpret ()
{
Return !Exp. interpret ();
}  
 
Public   Override   String Tostring ()
{
Return "(!"+Exp. tostring ()+")";
}  
}  
 
Public   Class Client
{
Public   Static   Void Main ()
{
Expression exp = New Or ( New And ( New Constant ( True ), New Constant ( False )),
New And ( New Constant ( True ), New Not ( New Constant ( False ))));
Console. writeline (exp. tostring () + " = " + Exp. interpret ());
}  
}  
}