For example:
// this.props.menuItems: MenuItem[];
// i.e. it is a typorama instance and lodash won't work
var selectedItem = _.find(this.props.menuItems, { id: this.props.selectedItemId });
One does this error very easily and it is not always immediately clear what's wrong. :-(
spoon lodash to throw error when it gets typorama object (just in development?)