syntax_data: {"ast_node_type":"other","tokens":[{"end":79,"kind":"keyword","start":0,"text":"///"}]}
source_snippet:     /// shape of `fn(tupled_inputs, resume_ty) -> (return_ty, yield_ty)`, where
context_before:     /// coroutine-closure. This signature parts type will have the general
context_after:     /// `resume_ty`, `return_ty`, and `yield_ty` are the respective types for the