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//@ known-bug: #116519
#![allow(incomplete_features)]
#![feature(generic_const_exprs)]
trait Ret {
type R;
}
struct Cond<const PRED: bool, U, V>(std::marker::PhantomData<U>, std::marker::PhantomData<V>);
impl<U, V> Ret for Cond<true, U, V> {
type R = U;
}
impl<U, V> Ret for Cond<false, U, V> {
type R = V;
}
struct RobinHashTable<
const MAX_LENGTH: usize,
CellIdx = <Cond<{ MAX_LENGTH < 65535 }, u16, u32> as Ret>::R,
> {
_idx: CellIdx,
}
impl<CellIdx> RobinHashTable<MAX_LENGTH, CellIdx> {
fn new() -> Self {
Self {
_idx: CellIdx { MAX_LENGTH },
}
}
}
impl<CellIdx> HashMapBase<CellIdx> {
fn new() -> Self {
Self {
_idx: CellIdx { 0 },
}
}
}
impl<CellIdx> HashMapBase<CellIdx> for RobinHashTable<MAX_LENGTH, CellIdx> {
fn hash<H: Hash + Hasher>(&self,
) -> H {
self._idx.hash()
}
fn eq(&self, other: &Self) -> bool {
self._idx.eq(other._idx)
}
}
impl<CellIdx> HashMapBase<CellIdx> for RobinHashTable<MAX_LENGTH, CellIdx> {
fn hash<H: Hash + Hasher>(&self, other: &Self) -> H {
self._idx.hash(other._idx)
}
fn eq(&self, other: &Self) -> bool {
self._idx.eq(other._idx)
}
}
#[test]
fn test_size_of_robin_hash_table() {
use std::mem::size_of;
println!("{}", size_of::<RobinHashTable<1024>>());
println!("{}", size_of::<RobinHashTable<65536>>());
}
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