use std::ops::{Index, IndexMut};
#[derive(Debug, PartialEq, Eq)]
pub struct MinusPlus<T> {
pub minus: T,
pub plus: T,
}
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum MinusPlusIndex {
Minus,
Plus,
}
pub use MinusPlusIndex::*;
impl<T> Index<MinusPlusIndex> for MinusPlus<T> {
type Output = T;
fn index(&self, side: MinusPlusIndex) -> &Self::Output {
match side {
Minus => &self.minus,
Plus => &self.plus,
}
}
}
impl<T> IndexMut<MinusPlusIndex> for MinusPlus<T> {
fn index_mut(&mut self, side: MinusPlusIndex) -> &mut Self::Output {
match side {
Minus => &mut self.minus,
Plus => &mut self.plus,
}
}
}
impl<T> MinusPlus<T> {
pub fn new(minus: T, plus: T) -> Self {
MinusPlus { minus, plus }
}
}
impl<T: Default> Default for MinusPlus<T> {
fn default() -> Self {
Self {
minus: T::default(),
plus: T::default(),
}
}
}