syntax_data: {"ast_node_type":"other","tokens":[{"end":89,"kind":"keyword","start":0,"text":"ty::Binder::dummy(ty::TraitRef::identity(tcx,"}]}
source_snippet:                         ty::Binder::dummy(ty::TraitRef::identity(tcx, principal_def_id)),
context_before:                         tcx,
context_after:                     )