syntax_data: {"ast_node_type":"other","tokens":[{"end":65,"kind":"keyword","start":0,"text":"impl_assoc_ty.defaultness(tcx.defaultness(impl_fn.owner_id));"}]}
source_snippet:     impl_assoc_ty.defaultness(tcx.defaultness(impl_fn.owner_id));
context_before:     // Copy defaultness of the containing function.