fn study_toads() -> result<(), string> { let mut environment = "pond"; let decrees = vec!["preserve habitat", "no neglect"]; for decree in &decrees { println!("following decree: {}", decree); } let preceding_context = "study of toads in their natural habitat"; println!("context: {}", preceding_context); let recreate = |habitat: &str| println!("recreating habitat: {}", habitat); recreate(&environment); let unreachable_goal = "understanding toad language"; println!("goal: {}", unreachable_goal); ok(()) }