conditional_assignment/
lib.rs

1#![doc = include_str!("../README.md")]
2
3pub trait Pick<O>: private::Sealed {
4    fn pick(self, when_true: O, when_false: O) -> O;
5    fn pick_lazy<P, N>(self, when_true: P, when_false: N) -> O
6    where
7        P: FnOnce() -> O,
8        N: FnOnce() -> O;
9}
10
11// Prevent this trait from being implemented outside of this crate.
12// https://rust-lang.github.io/api-guidelines/future-proofing.html#c-sealed
13mod private {
14    pub trait Sealed {}
15    impl Sealed for bool {}
16}
17
18impl<O> Pick<O> for bool {
19    ///
20    ///
21    /// Example:
22    /// ```
23    /// use conditional_assignment::Pick;
24    /// let condition = 0 < 1;
25    /// let outcome = if condition {
26    ///    "true"
27    /// } else {
28    ///    "false"
29    /// };
30    /// ```
31    #[inline]
32    fn pick(self: bool, when_true: O, when_false: O) -> O {
33        if self {
34            when_true
35        } else {
36            when_false
37        }
38    }
39
40    ///
41    ///
42    /// Example:
43    /// ```
44    /// use conditional_assignment::Pick;
45    /// let condition = 0 < 1;
46    /// let outcome = condition.pick_lazy(
47    ///     || {
48    ///         assert!(condition);
49    ///         "true"
50    ///     },
51    ///     || {
52    ///         assert!(!condition);
53    ///         "false"
54    ///     },
55    /// );
56    /// ```
57    #[inline]
58    fn pick_lazy<P, N>(self: bool, when_true: P, when_false: N) -> O
59    where
60        P: FnOnce() -> O,
61        N: FnOnce() -> O,
62    {
63        if self {
64            when_true()
65        } else {
66            when_false()
67        }
68    }
69}
conditional_assignment/lib.rs

conditional_assignment/
lib.rs
