pub trait Format {
// Provided methods
fn rfmt_infix(s: &str, args: &ExprList) -> String
where Self: Sized { ... }
fn rfmt_infix_with(s: &str, _state: FormatState, args: &ExprList) -> String
where Self: Sized { ... }
fn rfmt(&self) -> String { ... }
fn rfmt_with(&self, _state: FormatState) -> String { ... }
fn rfmt_call(&self, args: &ExprList) -> String { ... }
fn rfmt_call_with(&self, _state: FormatState, _args: &ExprList) -> String { ... }
}