syntax_data: {"ast_node_type":"other","tokens":[{"end":53,"kind":"keyword","start":0,"text":"\"extra"}]}
source_snippet:         "extra data to put in each output filename"),
context_before:     extra_filename: String = (String::new(), parse_string, [UNTRACKED],
context_after:     force_frame_pointers: FramePointer = (FramePointer::MayOmit, parse_frame_pointer, [TRACKED],