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Diffstat (limited to 'src/year.rs')
| -rw-r--r-- | src/year.rs | 220 |
1 files changed, 220 insertions, 0 deletions
diff --git a/src/year.rs b/src/year.rs new file mode 100644 index 0000000..3b4fad9 --- /dev/null +++ b/src/year.rs @@ -0,0 +1,220 @@ +use core::ops::{Add, AddAssign, Sub, SubAssign}; + +use derive_more::{Display, FromStr}; + +#[cfg(feature = "serde")] +use serde::{Deserialize, Serialize}; + +/// A year value type, stored as an i32 +#[derive(Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash, Debug, FromStr, Display)] +#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))] +pub struct Year(i32); + +impl Year { + /// The latest year that can be represented + pub const MAX: Year = Year(i32::MAX); + + /// The earliest year that can be represented + pub const MIN: Year = Year(i32::MIN); + + /// An equivalent of `Year::from(i32)`, which can be run at compile-time + /// + /// # Example + /// + /// ``` + /// use botic::Year; + /// + /// const YEAR: Year = Year::from_i32(2021); + /// assert_eq!(2021, YEAR.as_i32()); + /// ``` + pub const fn from_i32(i: i32) -> Self { + Self(i) + } + + /// An equivalent of `Year::into` which can be run at compile-time + /// + /// # Example + /// + /// ``` + /// use botic::Year; + /// + /// const YEAR: Year = Year::from_i32(2021); + /// const YEAR_INT: i32 = YEAR.as_i32(); + /// assert_eq!(2021, YEAR_INT); + /// ``` + pub const fn as_i32(self) -> i32 { + self.0 + } + + /// Checked year addition. + /// Computes `self + rhs`, returning `None` if overflow occurred. + /// + /// # Example + /// + /// ``` + /// use botic::Year; + /// + /// assert_eq!(Some(Year::from(2022)), Year::from_i32(2021).checked_add(1)); + /// assert_eq!(None, Year::MAX.checked_add(1)); + /// ``` + pub const fn checked_add(self, rhs: i32) -> Option<Year> { + match self.0.checked_add(rhs) { + Some(year) => Some(Self(year)), + None => None, + } + } + + /// Calculates `self + rhs` + /// + /// Returns a tuple of the addition along with a boolean indicating + /// whether an arithmetic overflow would occur. If an overflow would have + /// occurred then the wrapped value is returned. + /// + /// # Example + /// + /// ``` + /// use botic::Year; + /// + /// assert_eq!((Year::from(2022), false), Year::from(2021).overflowing_add(1)); + /// assert_eq!((Year::MIN, true), Year::MAX.overflowing_add(1)); + /// ``` + pub const fn overflowing_add(self, rhs: i32) -> (Year, bool) { + let int_result = self.0.overflowing_add(rhs); + (Year(int_result.0), int_result.1) + } + + /// Saturating year addition. + /// Computes `self + rhs`, saturating at the bounds instead of overflowing. + /// + /// # Example + /// + /// ``` + /// use botic::Year; + /// + /// assert_eq!(Year::from(2022), Year::from(2021).saturating_add(1)); + /// assert_eq!(Year::MAX, Year::MAX.saturating_add(1)); + /// ``` + pub const fn saturating_add(self, rhs: i32) -> Year { + Year(self.0.saturating_add(rhs)) + } + + /// Wrapping (modular) addition. + /// Computes `self + rhs`, wrapping around at the boundary of the type. + /// + /// # Example + /// + /// ``` + /// use botic::Year; + /// + /// assert_eq!(Year::from(2022), Year::from(2021).wrapping_add(1)); + /// assert_eq!(Year::MIN, Year::MAX.wrapping_add(1)); + pub const fn wrapping_add(self, rhs: i32) -> Year { + Year(self.0.wrapping_add(rhs)) + } + + /// Checked year subtraction. + /// Computes `self - rhs`, returning `None` if overflow occurred. + /// + /// # Example + /// + /// ``` + /// use botic::Year; + /// + /// assert_eq!(Some(Year::from(2020)), Year::from_i32(2021).checked_sub(1)); + /// assert_eq!(None, Year::MIN.checked_sub(1)); + /// ``` + pub const fn checked_sub(self, rhs: i32) -> Option<Year> { + match self.0.checked_sub(rhs) { + Some(year) => Some(Self(year)), + None => None, + } + } + + /// Calculates `self - rhs` + /// + /// Returns a tuple of the subtraction along with a boolean indicating + /// whether an arithmetic overflow would occur. If an overflow would have + /// occurred then the wrapped value is returned. + /// + /// # Example + /// + /// ``` + /// use botic::Year; + /// + /// assert_eq!((Year::from(2020), false), Year::from(2021).overflowing_sub(1)); + /// assert_eq!((Year::MAX, true), Year::MIN.overflowing_sub(1)); + /// ``` + pub const fn overflowing_sub(self, rhs: i32) -> (Year, bool) { + let int_result = self.0.overflowing_sub(rhs); + (Year(int_result.0), int_result.1) + } + + /// Saturating year subtraction. + /// Computes `self - rhs`, saturating at the bounds instead of overflowing. + /// + /// # Example + /// + /// ``` + /// use botic::Year; + /// + /// assert_eq!(Year::from(2020), Year::from(2021).saturating_sub(1)); + /// assert_eq!(Year::MIN, Year::MIN.saturating_sub(1)); + /// ``` + pub const fn saturating_sub(self, rhs: i32) -> Year { + Year(self.0.saturating_sub(rhs)) + } + + /// Wrapping (modular) subtraction. + /// Computes `self - rhs`, wrapping around at the boundary of the type. + /// + /// # Example + /// + /// ``` + /// use botic::Year; + /// + /// assert_eq!(Year::from(2020), Year::from(2021).wrapping_sub(1)); + /// assert_eq!(Year::MAX, Year::MIN.wrapping_sub(1)); + pub const fn wrapping_sub(self, rhs: i32) -> Year { + Year(self.0.wrapping_sub(rhs)) + } +} + +impl From<i32> for Year { + fn from(i: i32) -> Self { + Self(i) + } +} + +impl From<Year> for i32 { + fn from(year: Year) -> Self { + year.0 + } +} + +impl<I: Into<i32>> Add<I> for Year { + type Output = Self; + + fn add(self, rhs: I) -> Self::Output { + Self(self.0 + rhs.into()) + } +} + +impl<I: Into<i32>> Sub<I> for Year { + type Output = Self; + + fn sub(self, rhs: I) -> Self::Output { + Self(self.0 - rhs.into()) + } +} + +impl AddAssign<i32> for Year { + fn add_assign(&mut self, rhs: i32) { + self.0 = self.0 + rhs + } +} + +impl SubAssign<i32> for Year { + fn sub_assign(&mut self, rhs: i32) { + self.0 = self.0 - rhs + } +} |