syntax_data: {"ast_node_type":"variable","tokens":[{"end":76,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:         let ty::Ref(region, _, mutbl) = *self.thir[args[0]].ty.kind() else {
context_before:         // `Deref(Mut)::deref(_mut)` and `Index(Mut)::index(_mut)`.
context_after:             span_bug!(span, "overloaded_place: receiver is not a reference");