code: function hasTypeAnnotation (path: NodePath): boolean {
    if (!path.node) {
      return false;
    }
    else if (path.node.typeAnnotation) {
      return true;
    }
    else if (path.isAssignmentPattern()) {
      return hasTypeAnnotation(path.get('left'));
    }
    else {
      return false;
    }
  }
docs: Determine whether the given node path has a type annotation or not.