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use std::path::PathBuf;
use rayon::iter::{IntoParallelIterator, ParallelIterator};
mod chunks;
mod counter;
mod key_finder;
pub use chunks::chunks;
pub use counter::{Counter, KeyCount};
pub use key_finder::KeyFinder;
pub fn top_few_from_stream(
path: PathBuf,
kf: &KeyFinder,
num: usize,
) -> anyhow::Result<Vec<KeyCount>> {
let total = chunks(path)?
.collect::<Vec<_>>()
.into_par_iter()
.map(|reader| {
let mut counter = Counter::new(None);
let mut s = String::new();
for ln in reader {
s.clear();
if let Ok(key) = kf.key(&ln, &mut s) {
counter.add(key, 1)
}
}
counter
})
.reduce(|| Counter::new(Some(num)), |l, r| l.merge(r));
Ok(total.top())
}