syntax_data: {"ast_node_type":"other","tokens":[{"end":52,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:                     // rely on that assumption here.
context_before:                     // assumption to the `param_env` of the default method. We also separately
context_after:                     let ty = self.tcx.type_of(alias_ty.def_id).instantiate(self.tcx, alias_ty.args);