{"ast_node_type":"variable","tokens":[{"end":48,"kind":"keyword","start":0,"text":"let"}]}
            let (mut lo, mut hi) = (0u64, 0u64);
        try_as_const_integral(v).and_then(|v| unsafe {
            let success = llvm::LLVMRustConstInt128Get(v, sign_ext, &mut hi, &mut lo);