syntax_data: {"ast_node_type":"other","tokens":[{"end":97,"kind":"keyword","start":0,"text":"///"}]}
source_snippet:     /// extract function takes three arguments: a string slice containing the source, an index in
context_before:     /// Extracts the source surrounding the given `Span` using the `extract_source` function. The
context_after:     /// the slice for the beginning of the span and an index in the slice for the end of the span.