3 use crate::marker::Destruct;
6 /// Returns `Some(t)` if the `bool` is [`true`](../std/keyword.true.html),
7 /// or `None` otherwise.
12 /// assert_eq!(false.then_some(0), None);
13 /// assert_eq!(true.then_some(0), Some(0));
15 #[stable(feature = "bool_to_option", since = "1.62.0")]
16 #[rustc_const_unstable(feature = "const_bool_to_option", issue = "91917")]
18 pub const fn then_some<T>(self, t: T) -> Option<T>
22 if self { Some(t) } else { None }
25 /// Returns `Some(f())` if the `bool` is [`true`](../std/keyword.true.html),
26 /// or `None` otherwise.
31 /// assert_eq!(false.then(|| 0), None);
32 /// assert_eq!(true.then(|| 0), Some(0));
34 #[stable(feature = "lazy_bool_to_option", since = "1.50.0")]
35 #[rustc_const_unstable(feature = "const_bool_to_option", issue = "91917")]
37 pub const fn then<T, F>(self, f: F) -> Option<T>
39 F: ~const FnOnce() -> T,
42 if self { Some(f()) } else { None }