shitbox/bitflags-mini/src/lib.rs
Nathan Fisher 06b88d2c24 Refactoring:
- Split into workspace crates
- Split into two binaries `corebox` and `hashbox`
- Add `mount` crate to workspace to prepare for third binary `utilbox`
2023-02-05 23:50:59 -05:00

63 lines
1.2 KiB
Rust

//! Minimal bitflags type implementation allowing to check if a set of flags
//! contains a specific flag. The type must implement Copy and Bitand with u32.
use core::ops::BitAnd;
pub trait BitFlags<T> {
fn contains(&self, rhs: T) -> bool;
}
impl<T, U> BitFlags<T> for U
where
U: BitAnd<T> + Copy,
T: BitAnd<U>,
<U as BitAnd<T>>::Output: PartialEq<u32>,
{
fn contains(&self, rhs: T) -> bool {
*self & rhs != 0
}
}
#[cfg(test)]
mod test {
use super::*;
#[derive(Clone, Copy)]
enum Flags {
A = 0b1,
B = 0b10,
C = 0b100,
}
impl BitAnd<Flags> for u32 {
type Output = u32;
fn bitand(self, rhs: Flags) -> Self::Output {
self & rhs as u32
}
}
impl BitAnd<u32> for Flags {
type Output = u32;
fn bitand(self, rhs: u32) -> Self::Output {
self as u32 & rhs
}
}
impl BitAnd for Flags {
type Output = u32;
fn bitand(self, rhs: Self) -> Self::Output {
self as u32 & rhs as u32
}
}
#[test]
fn contains() {
let num = 0b101;
assert!(num.contains(Flags::A));
assert!(!num.contains(Flags::B));
assert!(num.contains(Flags::C));
}
}