syntax_data: {"ast_node_type":"other","tokens":[{"end":47,"kind":"keyword","start":0,"text":"if"}]}
source_snippet:                 if unsizing_params.is_empty() {
context_before:                 let unsizing_params = tcx.unsizing_params_for_adt(def.did());
context_after:                     return Err(SelectionError::Unimplemented);