syntax_data: {"ast_node_type":"other","tokens":[{"end":70,"kind":"keyword","start":0,"text":"Some(LangItem::Sized)"}]}
source_snippet:                         Some(LangItem::Sized) => match pred.polarity {
context_before:                     match tcx.as_lang_item(pred.def_id()) {
context_after:                             ty::PredicatePolarity::Positive => {