packed_char/
u22.rs

1use core::{
2    borrow::Borrow,
3    fmt::{self, Display, Formatter},
4    ops::Deref,
5};
6
7/// A 22-bit unsigned integer.
8#[derive(Debug, Default, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
9pub struct U22(u32);
10
11impl Display for U22 {
12    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
13        write!(f, "{}", self.0)
14    }
15}
16
17impl U22 {
18    /// The largest value that can be expressed by this type
19    pub const MAX: u32 = !(u32::MAX << 22);
20
21    /// Creates a new 22-bit integer from the given 32-bit integer if it is small enough to fit.
22    ///
23    /// # Examples
24    ///
25    /// ```
26    /// # use packed_char::{U22, U22FromU32Error};
27    /// assert_eq!(U22::from_u32(42).map(U22::as_u32), Ok(42));
28    /// assert_eq!(U22::from_u32(U22::MAX).map(U22::as_u32), Ok(U22::MAX));
29    /// assert_eq!(U22::from_u32(U22::MAX + 1), Err(U22FromU32Error(U22::MAX + 1)));
30    /// ```
31    pub const fn from_u32(n: u32) -> Result<Self, U22FromU32Error> {
32        if n > Self::MAX {
33            Err(U22FromU32Error(n))
34        } else {
35            Ok(Self(n))
36        }
37    }
38
39    /// Creates a new 22-bit integer from the given 32-bit integer.
40    ///
41    /// # Safety
42    ///
43    /// The provided integer must be no greater than [`U22::MAX`].
44    ///
45    /// # Examples
46    ///
47    /// ```
48    /// # use packed_char::U22;
49    /// let u22 = unsafe { U22::from_u32_unchecked(42) };
50    /// assert_eq!(u22.as_u32(), 42);
51    /// ```
52    pub const unsafe fn from_u32_unchecked(n: u32) -> Self {
53        Self(n)
54    }
55
56    /// Gets the 22-bit integer as a 32-bit integer.
57    ///
58    /// # Examples
59    ///
60    /// ```
61    /// # use packed_char::U22;
62    /// let u22 = U22::from_u32(42).unwrap();
63    /// assert_eq!(u22.as_ref(), &42);
64    /// ```
65    pub const fn as_u32(self) -> u32 {
66        self.0
67    }
68}
69
70impl TryFrom<u32> for U22 {
71    type Error = U22FromU32Error;
72
73    fn try_from(n: u32) -> Result<Self, Self::Error> {
74        Self::from_u32(n)
75    }
76}
77
78impl From<U22> for u32 {
79    fn from(u22: U22) -> Self {
80        u22.0
81    }
82}
83
84impl AsRef<u32> for U22 {
85    fn as_ref(&self) -> &u32 {
86        &self.0
87    }
88}
89
90impl Borrow<u32> for U22 {
91    fn borrow(&self) -> &u32 {
92        &self.0
93    }
94}
95
96impl Deref for U22 {
97    type Target = u32;
98
99    fn deref(&self) -> &Self::Target {
100        &self.0
101    }
102}
103
104// TODO: Implement core::error::Error when stabilized
105
106/// Error type for 32-bit to 22-bit integer conversion.
107#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
108pub struct U22FromU32Error(
109    /// The `u32` that failed to be converted to a [`U22`].
110    pub u32,
111);
112
113impl Display for U22FromU32Error {
114    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
115        write!(f, "{} exceeds U22::MAX", self.0)
116    }
117}
packed_char/u22.rs

packed_char/
u22.rs
