syntax_data: {"ast_node_type":"variable","tokens":[{"end":43,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:     let (thir, expr) = tcx.thir_body(def)?;
context_before: pub(crate) fn check_tail_calls(tcx: TyCtxt<'_>, def: LocalDefId) -> Result<(), ErrorGuaranteed> {
context_after:     let thir = &thir.borrow();