syntax_data: {"ast_node_type":"import","tokens":[{"end":80,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:         // because only *auto traits* are allowed other than the principal trait
context_before:         // under the same binders as `Foo`. Currently, this doesn't matter,
context_after:         // and all auto traits don't have any generics. Two things could