{"ast_node_type":"other","tokens":[{"end":83,"kind":"keyword","start":0,"text":"tty.skip_binders().as_slice(Interner).first().and_then(|pred|"}]}
                    tty.skip_binders().as_slice(Interner).first().and_then(|pred| {
                let principal = |tty: &Binders<QuantifiedWhereClauses>| {
                        if let WhereClause::Implemented(tr) = pred.skip_binders() {