pub trait LangHelper: Debug {
// Required method
fn keyword(&self) -> &[&'static str];
// Provided methods
fn _get_relevant_text(&self, token: &Spanned<Token>, rope: &Rope) -> String { ... }
fn get_relevant_text(
&self,
token: &Spanned<Token>,
rope: &Rope,
) -> (String, Range<usize>) { ... }
}