syntax_data: {"ast_node_type":"other","tokens":[{"end":66,"kind":"keyword","start":0,"text":"match"}]}
source_snippet:         match self.0.write().try_insert(span, (var_span, false)) {
context_before:     pub fn insert(&self, span: Span, var_span: Span) -> bool {
context_after:             Ok(_) => true,