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//! We don't use `rand`, as that's too many things for us.
//!
//! We currently use oorandom instead, but it's missing these two utilities.
//! Perhaps we should switch to `fastrand`, or our own small PRNG, it's not like
//! we need anything more complicated than xor-shift.
pub fn shuffle<T>(slice: &mut [T], mut rand_index: impl FnMut(usize) -> usize) {
let mut remaining = slice.len() - 1;
while remaining > 0 {
let index = rand_index(remaining);
slice.swap(remaining, index);
remaining -= 1;
}
}
pub fn seed() -> u64 {
use std::collections::hash_map::RandomState;
use std::hash::{BuildHasher, Hasher};
RandomState::new().build_hasher().finish()
}
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