Expand description
The extsort crate exposes external sorting (i.e. on disk sorting) capability on arbitrarily sized iterator, even if the
generated content of the iterator doesn’t fit in memory. Once sorted, it returns a new sorted iterator.
In order to remain efficient for all implementations, extsort doesn’t handle serialization, but leaves that to the user.
Examples
extern crate extsort;
extern crate byteorder;
use extsort::*;
use byteorder::{ReadBytesExt, WriteBytesExt};
use std::io::{Read, Write};
#[derive(Debug, Eq, PartialEq, Ord, PartialOrd)]
struct MyStruct(u32);
impl Sortable<MyStruct> for MyStruct {
fn encode(item: &MyStruct, write: &mut Write) {
write.write_u32::<byteorder::LittleEndian>(item.0).unwrap();
}
fn decode(read: &mut Read) -> Option<MyStruct> {
read.read_u32::<byteorder::LittleEndian>()
.ok()
.map(MyStruct)
}
}
let sorter = ExternalSorter::new();
let reversed_data = (0..1000).rev().map(MyStruct).into_iter();
let sorted_iter = sorter.sort(reversed_data).unwrap();
let sorted_data: Vec<MyStruct> = sorted_iter.collect();
let expected_data = (0..1000).map(MyStruct).collect::<Vec<MyStruct>>();
assert_eq!(sorted_data, expected_data);