use_bound/
lib.rs

1#![forbid(unsafe_code)]
2#![doc = include_str!("../README.md")]
3
4//! Inclusive and exclusive bound primitives.
5
6pub mod prelude;
7
8#[derive(Debug, Clone, PartialEq, Eq)]
9pub enum LowerBound<T> {
10    Inclusive(T),
11    Exclusive(T),
12}
13
14impl<T: PartialOrd> LowerBound<T> {
15    #[must_use]
16    pub fn allows(&self, value: &T) -> bool {
17        match self {
18            Self::Inclusive(bound) => value >= bound,
19            Self::Exclusive(bound) => value > bound,
20        }
21    }
22
23    #[must_use]
24    pub const fn value(&self) -> &T {
25        match self {
26            Self::Inclusive(bound) | Self::Exclusive(bound) => bound,
27        }
28    }
29}
30
31#[derive(Debug, Clone, PartialEq, Eq)]
32pub enum UpperBound<T> {
33    Inclusive(T),
34    Exclusive(T),
35}
36
37impl<T: PartialOrd> UpperBound<T> {
38    #[must_use]
39    pub fn allows(&self, value: &T) -> bool {
40        match self {
41            Self::Inclusive(bound) => value <= bound,
42            Self::Exclusive(bound) => value < bound,
43        }
44    }
45
46    #[must_use]
47    pub const fn value(&self) -> &T {
48        match self {
49            Self::Inclusive(bound) | Self::Exclusive(bound) => bound,
50        }
51    }
52}
53
54#[must_use]
55pub const fn minimum<T>(value: T) -> LowerBound<T> {
56    LowerBound::Inclusive(value)
57}
58
59#[must_use]
60pub const fn exclusive_minimum<T>(value: T) -> LowerBound<T> {
61    LowerBound::Exclusive(value)
62}
63
64#[must_use]
65pub const fn maximum<T>(value: T) -> UpperBound<T> {
66    UpperBound::Inclusive(value)
67}
68
69#[must_use]
70pub const fn exclusive_maximum<T>(value: T) -> UpperBound<T> {
71    UpperBound::Exclusive(value)
72}
73
74#[cfg(test)]
75mod tests {
76    use super::{exclusive_minimum, maximum};
77
78    #[test]
79    fn bounds_apply_inclusive_and_exclusive_logic() {
80        let lower = exclusive_minimum(0);
81        let upper = maximum(10);
82
83        assert!(lower.allows(&1));
84        assert!(!lower.allows(&0));
85        assert!(upper.allows(&10));
86    }
87}
use_bound/lib.rs

use_bound/
lib.rs
