syntax_data: {"ast_node_type":"other","tokens":[{"end":86,"kind":"keyword","start":0,"text":"///"}]}
source_snippet:     /// general for soundness of specialization. However, we *could* allow projections
context_before:     /// Non-`default` ("final") types are always projected. This is necessary in
context_after:     /// in fully-monomorphic cases. We choose not to, because we prefer for `default type`