{"ast_node_type":"variable","tokens":[{"end":80,"kind":"keyword","start":0,"text":"let"}]}
                let niche_start_val = ImmTy::from_uint(niche_start, tag_layout);
                let tag_layout = self.layout_of(tag_layout.primitive().to_int_ty(*self.tcx))?;
                let variant_index_relative_val =