syntax_data: {"ast_node_type":"other","tokens":[{"end":42,"kind":"keyword","start":0,"text":"trace!(\"checking"}]}
source_snippet:         trace!("checking const {:?}", ct);
context_before:     fn fold_const(&mut self, ct: ty::Const<'tcx>) -> ty::Const<'tcx> {
context_after:         // Find a const parameter