docs: private static LookupResult tryAsScript(String name, CompilationUnit compilationUnit, ClassNode oldClass) {
          LookupResult lr = null;
          if (oldClass!=null) {
              lr = new LookupResult(null, oldClass);
          }
          
          if (name.startsWith("java.")) return lr;
          //TODO: don't ignore inner static classes completely
          if (name.indexOf('$') != -1) return lr;
          
          // try to find a script from classpath*/
          GroovyClassLoader gcl = compilationUnit.getClassLoader();
          URL url = null;
          try {
              url = gcl.getResourceLoader().loadGroovySource(name);
          } catch (MalformedURLException e) {
              // fall through and let the URL be null
          }
          if (url != null && ( oldClass==null || isSourceNewer(url, oldClass))) {
              SourceUnit su = compilationUnit.addSource(url);
              return new LookupResult(su,null);
          }
          return lr;
      }