syntax_data: {"ast_node_type":"other","tokens":[{"end":80,"kind":"keyword","start":0,"text":"///"}]}
source_snippet:     /// target features. This is `true` by default, and `false` for targets like
context_before:     /// typically required if a target can be compiled with a mixed set of
context_after:     /// wasm32 where the whole program either has simd or not.