Finished up the keyword resolution issue and fixed for, while and until. Other tags still need work.

__for.cpp

@@ -5,20 +5,24 @@
 namespace jet {
 
    __for::__for(coreutils::ZString &in, coreutils::MString &parentOut, Global &global, Tag *parent) : Tag(in, parentOut, global, parent) {
-      double counter = 0.0f;
-      double end = 0.0f;
-      double step = 0.0f;
+      double counter = 0.0f;   
       bool nameDefined = variableDefined("name");
-      if(variableDefined(coreutils::ZString("start"))) {	   
+      if(variableDefined("start")) {
+	 resolveKeyword("start");
 	 counter = variables["start"].asDouble();
+	 variables["start"].reset();
       }
-      if(variableDefined(coreutils::ZString("end"))) {	   
-	 end = variables["end"].asDouble();
-      }
-      if(variableDefined(coreutils::ZString("step"))) {	   
-	 step = variables["step"].asDouble();
-      }
-      for(double ix = counter; ix <= end; ix += step) {
+      if(variableDefined("end")) 
+	resolveKeyword("end");
+      else
+	throw coreutils::Exception("for tag requires end keyword.");
+      if(variableDefined("step")) 
+	resolveKeyword("step");
+      else
+	throw coreutils::Exception("for tag requires step keyword.");
+      for(double ix = counter; ix <= variables["end"].asDouble(); ix += variables["step"].asDouble()) {
+	 variables["end"].reset();
+	 variables["step"].reset();	 
 	 if(nameDefined) 
 	   variables[variables["name"]] = ix;	 
 	 processContainer(container);