syntax_data: {"ast_node_type":"function","tokens":[{"end":98,"kind":"keyword","start":0,"text":"fn"}]}
source_snippet:     fn new_generic_adt(tcx: TyCtxt<'tcx>, wrapper_def_id: DefId, ty_param: Ty<'tcx>) -> Ty<'tcx> {
context_after:         let adt_def = tcx.adt_def(wrapper_def_id);