syntax_data: {"ast_node_type":"variable","tokens":[{"end":45,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:                 let own_existential_entries =
context_before:                 // Lookup the shape of vtable for the trait.
context_after:                     tcx.own_existential_vtable_entries(existential_trait_ref.def_id);