syntax_data: {"ast_node_type":"variable","tokens":[{"end":86,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:                 let binder = &self.binders[self.binders.len() - 1 - debruijn.index()];
context_before:             ty::ReBound(debruijn, ty::BoundRegion { var, kind: ty::BoundRegionKind::Anon }) => {
context_after:                 let depth = binder.lifetime_depths.start + var.as_u32();