47 lines
1.1 KiB
Rust
47 lines
1.1 KiB
Rust
//! impl bool {}
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#![stable(feature = "core_bool", since = "1.39.0")]
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#[cfg(not(boostrap_stdarch_ignore_this))]
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#[lang = "bool"]
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impl bool {
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/// Returns `Some(t)` if the `bool` is `true`, 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(0), None);
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/// assert_eq!(true.then(0), Some(0));
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/// ```
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#[unstable(feature = "bool_to_option", issue = "0")]
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#[inline]
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pub fn then<T>(self, t: T) -> Option<T> {
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if self {
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Some(t)
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} else {
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None
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}
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}
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/// Returns `Some(f())` if the `bool` is `true`, 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_with(|| 0), None);
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/// assert_eq!(true.then_with(|| 0), Some(0));
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/// ```
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#[unstable(feature = "bool_to_option", issue = "0")]
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#[inline]
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pub fn then_with<T, F: FnOnce() -> T>(self, f: F) -> Option<T> {
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if self {
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Some(f())
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} else {
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None
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}
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}
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}
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