syntax_data: {"ast_node_type":"variable","tokens":[{"end":40,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:         let expr = &$self.thir[expr_id];
context_before:         let expr_id = $self.preparse($expr_id);
context_after:         tracing::debug!("Trying to parse {:?} as {}", expr.kind, $expected);