Fixed expressions to be able to do math with nested expressions.

__if.cpp

@@ -1,7 +1,7 @@
 #include "__if.h"
 #include "Exception.h"
 #include <iostream>
-#include "Expression.h"
+#include "Operand.h"
 
 namespace jet {
 
@@ -15,7 +15,7 @@ namespace jet {
 	   throw coreutils::Exception("Either value1 or expr can be specified but not both.");
 	 if(variableDefined("value2")) {
 	    if(variableDefined("type")) {
-	       result = Expression(variables["expr"]);
+	       
 	    } else
 	      throw coreutils::Exception("type expected if value1 and value2 specified.");
 	 } else
@@ -37,8 +37,7 @@ namespace jet {
 	   throw coreutils::Exception("value2 should not be specified with expr.");
 	 if(variableDefined("type"))
 	   throw coreutils::Exception("type should not be specified with expr.");
-	 result = Expression(variables["expr"]);
-	 booleanResult = true;
+	 booleanResult = Operand(variables["expr"]).boolean;
       }
       if(booleanResult) 
 	processContainer(container);