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//! impl bool {} #[cfg(not(bootstrap))] #[lang = "bool"] impl bool { /// Returns `Some(t)` if the `bool` is `true`, or `None` otherwise. /// /// # Examples /// /// ``` /// #![feature(bool_to_option)] /// /// assert_eq!(false.then(0), None); /// assert_eq!(true.then(0), Some(0)); /// ``` #[unstable(feature = "bool_to_option", issue = "64260")] #[inline] pub fn then<T>(self, t: T) -> Option<T> { if self { Some(t) } else { None } } /// Returns `Some(f())` if the `bool` is `true`, or `None` otherwise. /// /// # Examples /// /// ``` /// #![feature(bool_to_option)] /// /// assert_eq!(false.then_with(|| 0), None); /// assert_eq!(true.then_with(|| 0), Some(0)); /// ``` #[unstable(feature = "bool_to_option", issue = "64260")] #[inline] pub fn then_with<T, F: FnOnce() -> T>(self, f: F) -> Option<T> { if self { Some(f()) } else { None } } }