syntax_data: {"ast_node_type":"other","tokens":[{"end":56,"kind":"keyword","start":0,"text":"sig.output().map_bound(|output_ty|"}]}
source_snippet:                     sig.output().map_bound(|output_ty| {
context_before:                     tcx,
context_after:                         ty::TraitRef::new(tcx, sized_trait_def_id, [output_ty])