syntax_data: {"ast_node_type":"variable","tokens":[{"end":88,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:                 let not_info = NotInfo { is_flipped: !not_info.is_flipped, ..not_info };
context_before:                 // Invert the `is_flipped` flag for the contents of this `!`.
context_after:                 self.visit_with_not_info(thir, arg, not_info);