docs: public Object use(Closure closure) {
          // grab existing meta (usually adaptee but we may have nested use calls)
          MetaClass origMetaClass = registry.getMetaClass(theClass);
          registry.setMetaClass(theClass, this);
          try {
              return closure.call();
          } finally {
              registry.setMetaClass(theClass, origMetaClass);
          }
      }