{"ast_node_type":"other","tokens":[{"end":86,"kind":"keyword","start":0,"text":"FnKind::Fn(_,"}]}
            FnKind::Fn(_, _, f) => TildeConstReason::Function { ident: f.ident.span },
        let disallowed = (!tilde_const_allowed).then(|| match fk {
            FnKind::Closure(..) => TildeConstReason::Closure,