{"ast_node_type":"variable","tokens":[{"end":82,"kind":"keyword","start":0,"text":"let"}]}
        let source = Cell::new(CandidateSource::ParamEnv(ParamEnvSource::Global));
        // by using a `Cell` here. We only ever write into it inside of `match_assumption`.
        ecx.probe(|result: &QueryResult<I>| inspect::ProbeKind::TraitCandidate {