syntax_data: {"ast_node_type":"other","tokens":[{"end":83,"kind":"keyword","start":0,"text":".rposition(|breakable_scope|"}]}
source_snippet:                 .rposition(|breakable_scope| breakable_scope.region_scope == scope)
context_before:                 .iter()
context_after:                 .unwrap_or_else(|| span_bug!(span, "no enclosing breakable scope found"))