syntax_data: {"ast_node_type":"other","tokens":[{"end":43,"kind":"keyword","start":0,"text":"for"}]}
source_snippet:         for cls in &mut cls[first..=last] {
context_before:         let last = ((off.bytes() + layout.size.bytes() - 1) / 8) as usize;
context_after:             *cls = Some(cls.map_or(c, |old| old.min(c)));