47 lines
1.2 KiB
Rust
47 lines
1.2 KiB
Rust
//! impl bool {}
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use crate::marker::Destruct;
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impl bool {
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/// Returns `Some(t)` if the `bool` is [`true`](../std/keyword.true.html),
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/// or `None` otherwise.
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///
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/// # Examples
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///
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/// ```
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/// #![feature(bool_to_option)]
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///
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/// assert_eq!(false.then_some(0), None);
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/// assert_eq!(true.then_some(0), Some(0));
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/// ```
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#[unstable(feature = "bool_to_option", issue = "80967")]
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#[rustc_const_unstable(feature = "const_bool_to_option", issue = "91917")]
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#[inline]
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pub const fn then_some<T>(self, t: T) -> Option<T>
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where
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T: ~const Destruct,
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{
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if self { Some(t) } else { None }
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}
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/// Returns `Some(f())` if the `bool` is [`true`](../std/keyword.true.html),
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/// or `None` otherwise.
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///
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/// # Examples
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///
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/// ```
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/// assert_eq!(false.then(|| 0), None);
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/// assert_eq!(true.then(|| 0), Some(0));
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/// ```
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#[stable(feature = "lazy_bool_to_option", since = "1.50.0")]
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#[rustc_const_unstable(feature = "const_bool_to_option", issue = "91917")]
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#[inline]
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pub const fn then<T, F>(self, f: F) -> Option<T>
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where
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F: ~const FnOnce() -> T,
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F: ~const Destruct,
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{
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if self { Some(f()) } else { None }
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}
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}
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