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use std::ops::Rem;
use crate::{Z32, Z64};
use num_traits::{AsPrimitive, Bounded, Inv, Num, One, Pow, Unsigned, Zero};
use paste::paste;
macro_rules! impl_traits {
( $($z:literal), *) => {
$(
paste!{
impl<const P: [<u $z>]> Bounded for [<Z $z>]<P> {
fn min_value() -> Self {
Self::MIN
}
fn max_value() -> Self {
Self::MAX
}
}
impl<const P: [<u $z>]> Zero for [<Z $z>]<P> {
fn zero() -> Self {
assert!(P > 0);
Self::new_unchecked(0)
}
fn is_zero(&self) -> bool {
self.repr().is_zero()
}
}
impl<const P: [<u $z>]> One for [<Z $z>]<P> {
fn one() -> Self {
assert!(P > 1);
Self::new_unchecked(1)
}
fn is_one(&self) -> bool {
self.repr().is_one()
}
}
impl<const P: [<u $z>]> Inv for [<Z $z>]<P> {
type Output = Self;
fn inv(self) -> Self {
[<Z $z>]::<P>::inv(&self)
}
}
impl<const P: [<u $z>]> Unsigned for [<Z $z>]<P> {}
impl<const P: [<u $z>]> Num for [<Z $z>]<P> {
type FromStrRadixErr = <[<u $z>] as Num>::FromStrRadixErr;
fn from_str_radix(
str: &str,
radix: u32,
) -> Result<Self, Self::FromStrRadixErr> {
Ok(Self::new([<i $z>]::from_str_radix(str, radix)?))
}
}
impl<const P: [<u $z>]> Rem for [<Z $z>]<P> {
type Output = Self;
fn rem(self, _modulus: Self) -> Self::Output {
Self::zero()
}
}
impl<const P: [<u $z>]> Pow<i8> for [<Z $z>]<P> {
type Output = Self;
fn pow(self, exp: i8) -> Self::Output {
if exp < 0 {
self.pow((-exp) as u8).inv()
} else {
self.pow(exp as u8)
}
}
}
impl<const P: [<u $z>]> Pow<i16> for [<Z $z>]<P> {
type Output = Self;
fn pow(self, exp: i16) -> Self::Output {
if exp < 0 {
self.pow((-exp) as u16).inv()
} else {
self.pow(exp as u16)
}
}
}
impl<const P: [<u $z>]> Pow<i32> for [<Z $z>]<P> {
type Output = Self;
fn pow(self, exp: i32) -> Self::Output {
if exp < 0 {
self.pow((-exp) as u32).inv()
} else {
self.pow(exp as u32)
}
}
}
impl<const P: [<u $z>]> Pow<i64> for [<Z $z>]<P> {
type Output = Self;
fn pow(self, exp: i64) -> Self::Output {
if exp < 0 {
self.pow((-exp) as u64).inv()
} else {
self.pow(exp as u64)
}
}
}
impl<const P: [<u $z>]> Pow<i128> for [<Z $z>]<P> {
type Output = Self;
fn pow(self, exp: i128) -> Self::Output {
if exp < 0 {
self.pow((-exp) as u128).inv()
} else {
self.pow(exp as u128)
}
}
}
}
)*
}
}
impl_traits! {32, 64}
// TODO: code duplication with Self::powu
macro_rules! impl_powu {
( $( $x:ty ),* ) => {
$(
// TODO: put inside impl_trait as soon as
// https://github.com/rust-lang/rust/issues/35853
// is resolved
impl<const P: u64> Pow<$x> for Z64<P> {
type Output = Self;
fn pow(mut self, mut exp: $x) -> Self::Output {
assert!(P > 1);
let mut res = Self::new_unchecked(1);
while exp > 0 {
if exp & 1 != 0 {
res *= self
};
self *= self;
exp /= 2;
}
res
}
}
impl<const P: u32> Pow<$x> for Z32<P> {
type Output = Self;
fn pow(mut self, mut exp: $x) -> Self::Output {
assert!(P > 1);
let mut res = Self::new_unchecked(1);
while exp > 0 {
if exp & 1 != 0 {
res *= self
};
self *= self;
exp /= 2;
}
res
}
}
impl<const P: u64> Pow<$x> for &Z64<P> {
type Output = Z64<P>;
fn pow(self, exp: $x) -> Self::Output {
(*self).pow(exp)
}
}
impl<const P: u32> Pow<$x> for &Z32<P> {
type Output = Z32<P>;
fn pow(self, exp: $x) -> Self::Output {
(*self).pow(exp)
}
}
)*
};
}
impl_powu!(u8, u16, u32, u64, u128);
macro_rules! impl_as_primitive {
( $( $x:ty ),* ) => {
$(
// TODO: put inside impl_trait as soon as
// https://github.com/rust-lang/rust/issues/35853
// is resolved
impl<const P: u64> AsPrimitive<$x> for Z64<P> {
fn as_(self) -> $x {
self.repr() as $x
}
}
impl<const P: u32> AsPrimitive<$x> for Z32<P> {
fn as_(self) -> $x {
self.repr() as $x
}
}
)*
};
}
impl_as_primitive!(i8, u8, i16, u16, i32, u32, i64, u64, i128, u128);
#[cfg(test)]
mod tests {
use super::*;
const PRIMES: [u64; 3] = [3, 443619635352171979, 1152921504606846883];
#[test]
fn bounded() {
use crate::Z64;
assert_eq!(
Z64::<{ PRIMES[0] }>::min_value(),
Z64::<{ PRIMES[0] }>::new(0)
);
assert_eq!(
Z64::<{ PRIMES[0] }>::max_value(),
Z64::<{ PRIMES[0] }>::new(-1)
);
assert_eq!(
Z64::<{ PRIMES[1] }>::min_value(),
Z64::<{ PRIMES[1] }>::new(0)
);
assert_eq!(
Z64::<{ PRIMES[1] }>::max_value(),
Z64::<{ PRIMES[1] }>::new(-1)
);
assert_eq!(
Z64::<{ PRIMES[2] }>::min_value(),
Z64::<{ PRIMES[2] }>::new(0)
);
assert_eq!(
Z64::<{ PRIMES[2] }>::max_value(),
Z64::<{ PRIMES[2] }>::new(-1)
);
}
}