syntax_data: {"ast_node_type":"other","tokens":[{"end":43,"kind":"keyword","start":0,"text":"src.get(start_index..end_index)"}]}
source_snippet:             src.get(start_index..end_index)
context_before:         self.span_to_source(sp, |src, start_index, end_index| {
context_after:                 .map(|s| s.to_string())