fayalite/crates/fayalite/src/util/const_usize.rs
2024-08-16 17:44:28 -07:00

29 lines
846 B
Rust

// SPDX-License-Identifier: LGPL-3.0-or-later
// See Notices.txt for copyright information
use std::{fmt::Debug, hash::Hash};
mod sealed {
pub trait Sealed {}
}
/// the only implementation is `ConstUsize<Self::VALUE>`
pub trait GenericConstUsize:
sealed::Sealed + Copy + Ord + Hash + Default + Debug + 'static + Send + Sync
{
const VALUE: usize;
}
#[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, Default)]
pub struct ConstUsize<const VALUE: usize>;
impl<const VALUE: usize> Debug for ConstUsize<VALUE> {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
f.debug_tuple("ConstUsize").field(&Self::VALUE).finish()
}
}
impl<const VALUE: usize> sealed::Sealed for ConstUsize<VALUE> {}
impl<const VALUE: usize> GenericConstUsize for ConstUsize<VALUE> {
const VALUE: usize = VALUE;
}