Model: cs+=Company* employees+=Emp* (block+=Head ";")+
; 

Named:
	Company | Emp | empId
;

Head:
	headable=[Named] tail=Tail
;

Tail:
	{Tail}":" tailable=[Named] (tail=Tail)?
;

Company: c='Company' name=ID '{' emp+=Emp+ '}';

Emp: r='Emp' name=ID '{' empIdName+= empId* '}'';' ; 
empId: 'Employee_id' name=ID;

public class MyDslNameProvider extends SimpleNameProvider {

}

public class MyDslRuntimeModule extends org.xtext.example.mydsl.AbstractMyDslRuntimeModule {

	@Override
	public Class<? extends IQualifiedNameProvider> bindIQualifiedNameProvider() {
		return MyDslNameProvider.class;
	}
	
}

public class MyDslScopeProvider extends AbstractDeclarativeScopeProvider {

	IScope scope_Head_headable(EObject ctx, EReference ref) {
		return new FilteringScope(delegateGetScope(ctx, ref), new Predicate<IEObjectDescription>() {

			@Override
			public boolean apply(IEObjectDescription input) {
				return EcoreUtil2.isAssignableFrom(MyDslPackage.Literals.COMPANY, input.getEClass())
					|| EcoreUtil2.isAssignableFrom(MyDslPackage.Literals.EMP, input.getEClass());
			}
			
		});
	}
	
	IScope scope_Tail_tailable(EObject ctx, EReference ref) {
		EObject container = ctx.eContainer();
		if (container instanceof Head) {
			Head head = (Head)container;
			if (head.getHeadable() instanceof Company) {
				return Scopes.scopeFor(((Company)head.getHeadable()).getEmp());
			}
			if (head.getHeadable() instanceof Emp) {
				return Scopes.scopeFor(((Emp)head.getHeadable()).getEmpIdName());
			}
			return IScope.NULLSCOPE;
		} else if (container instanceof Tail) {
			Tail tail = (Tail)container;
			if (tail.getTailable() instanceof Emp) {
				return Scopes.scopeFor(((Emp)tail.getTailable()).getEmpIdName());
			}
			return IScope.NULLSCOPE;
		}
		return IScope.NULLSCOPE;
	}
	
}