{"ast_node_type":"other","tokens":[{"end":50,"kind":"keyword","start":0,"text":"(ty::Uint(ty::UintTy::U32),"}]}
        (ty::Uint(ty::UintTy::U32), ty::Char) => (
        // u32 → char
            Some(vec![(callee_span, "char::from_u32_unchecked".to_string())]),