syntax_data: {"ast_node_type":"other","tokens":[{"end":27,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:         // base is an enum.
context_before:         // projection than `enum_place`. This additional projection must be a downcast since the
context_after:         let (downcast, base_proj) = variant_path.place.projection.split_last().unwrap();