syntax_data: {"ast_node_type":"other","tokens":[{"end":26,"kind":"keyword","start":0,"text":"Ok(_)"}]}
source_snippet:             Ok(_) => true,
context_before:         match self.0.write().try_insert(span, (var_span, false)) {
context_after:             Err(entry) => entry.entry.get().0 == var_span,