syntax_data: {"ast_node_type":"other","tokens":[{"end":95,"kind":"keyword","start":0,"text":".rposition(|const_continuable_scope|"}]}
source_snippet:             .rposition(|const_continuable_scope| const_continuable_scope.region_scope == scope)
context_before:             .iter()
context_after:             .unwrap_or_else(|| span_bug!(span, "no enclosing const-continuable scope found"));