syntax_data: {"ast_node_type":"other","tokens":[{"end":82,"kind":"keyword","start":0,"text":"self.scopes.last().expect(\"topmost_scope:"}]}
source_snippet:         self.scopes.last().expect("topmost_scope: no scopes present").region_scope
context_before:     fn topmost(&self) -> region::Scope {
context_after:     }