Liam Watts

@liam271.bsky.social

Software engineer and language leaner I do backend, data engineering, some frontend, some AI. Love learning new things and so I've picked up languages like C#, Haskell, Rust, and Japanese https://github.com/Wattsy2020

impl<T, I: Iterator<Item = T>> Iterator for PairwiseResults<T, I> {
type Item = Pair<T>;

fn next(&mut self) -> Option<Self::Item> {
match self.iterator.next() {
None => self.prev.take().map(Last),
Some(next) => {
match self.prev.take() {
None => {
self.prev = Some(next);
match self.prev.take() {
Some(val) => Some(First(val)),
None => unreachable!(), // This should not happen
}
}
Some(prev) => {
self.prev = Some(next);
match self.prev.take() {
Some(val) => Some(Middle(prev, val)),
None => unreachable!(), // This should not happen
}
}
}
}
}
}
}

impl<T, I: Iterator<Item = T>> Iterator for PairwiseResults<T, I>
where
T: Clone, // Add Clone bound if you need to clone the values
{
type Item = Pair<T>;

fn next(&mut self) -> Option<Self::Item> {
match self.iterator.next() {
None => {
let result = self.prev.take().map(Last);
result
},
Some(next) => {
let temp = self.prev.take();
self.prev = Some(next.clone()); // Clone here if needed, otherwise move
match temp {
None => Some(First(next)),
Some(prev) => Some(Middle(prev, next))
}
}
}
}
}

impl<'a, T, I: Iterator<Item = &'a T>> Iterator for PairwiseResults<'a, T, I> {
type Item = Pair<&'a T>;

fn next(&mut self) -> Option<Self::Item> {
match self.iterator.next() {
None => {
let result = self.prev.map(Last);
self.prev = None;
result
},
Some(next) => {
let temp = self.prev;
self.prev = Some(next);
match temp {
None => Some(First(next)),
Some(prev) => Some(Middle(prev, next))
}
}
}
}
}

$Implementing a trait for all Vectors of a type that implements that trait. impl<T: ToKafkaBytes> ToKafkaBytes for Vec<T> { // write the length of the array, then each item in the array fn to_kafka_bytes(self) -> impl IntoIterator<Item = u8> { let length = VarInt::new((self.len() + 1) as u32); let vec_as_bytes = self.into_iter().flat_map(|item| item.to_kafka_bytes()); length.to_kafka_bytes().into_iter().chain(vec_as_bytes) } }$