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use std::ops::BitAnd;
pub trait Sortable
{
type Item;
fn sort_by_key_b<Key, Func>(&mut self, func: Func)
where
Func: FnMut(&Self::Item) -> Key,
Key: Ord;
}
impl<Item> Sortable for [Item]
{
type Item = Item;
fn sort_by_key_b<Key, Func>(&mut self, func: Func)
where
Func: FnMut(&Self::Item) -> Key,
Key: Ord,
{
self.sort_by_key(func);
}
}
impl<Item, const LENGTH: usize> Sortable for [Item; LENGTH]
{
type Item = Item;
fn sort_by_key_b<Key, Func>(&mut self, func: Func)
where
Func: FnMut(&Self::Item) -> Key,
Key: Ord,
{
self.sort_by_key(func);
}
}
impl<Item> Sortable for Vec<Item>
{
type Item = Item;
fn sort_by_key_b<Key, Func>(&mut self, func: Func)
where
Func: FnMut(&Self::Item) -> Key,
Key: Ord,
{
self.sort_by_key(func);
}
}
#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
pub struct BitMask<Value>
{
mask: Value,
}
impl BitMask<u64>
{
#[must_use]
pub const fn new(mask: u64) -> Self
{
Self { mask }
}
pub const fn value(self) -> u64
{
self.mask
}
/// Prepares a bitfield value in the range of bits specified by this `BitMask`.
#[must_use]
pub const fn field_prep(self, field_value: u64) -> u64
{
((field_value) << self.mask.trailing_zeros()) & (self.mask)
}
}
impl BitAnd<u64> for BitMask<u64>
{
type Output = u64;
fn bitand(self, rhs: u64) -> Self::Output
{
self.mask & rhs
}
}
pub trait NumberExt: Sized
{
/// Returns a range of bits (field) specified by the provided [`BitMask`].
fn field_get(self, field_mask: BitMask<Self>) -> Self;
}
impl NumberExt for u64
{
fn field_get(self, field_mask: BitMask<Self>) -> Self
{
(field_mask & self) >> field_mask.value().trailing_zeros()
}
}
macro_rules! gen_mask_64 {
($low: literal..=$high: literal) => {
const {
if $high <= $low {
panic!("High bit index cannot be less than or equal to low bit index");
}
(((!0u64) - (1u64 << ($low)) + 1)
& (!0u64 >> (u64::BITS as u64 - 1 - ($high))))
}
};
}
pub(crate) use gen_mask_64;
#[cfg(test)]
mod tests
{
use super::BitMask;
use crate::util::NumberExt;
#[test]
fn field_get_works()
{
assert_eq!(0b11011u64.field_get(BitMask::new(0b11100)), 0b00110);
}
#[test]
fn bitmask_field_prep_works()
{
assert_eq!(BitMask::new(0b11000).field_prep(3), 0b11000);
}
}
|
