use crate::internals::stream_controller::*;
use crate::prelude::*;
use std::{
marker::PhantomData,
sync::{Arc, RwLock},
};
#[derive(Clone)]
pub struct Max<Item> {
_item: PhantomData<Item>,
}
impl<'a, Item> Max<Item>
where
Item: Clone + Send + Sync + PartialOrd,
{
pub fn new() -> Max<Item> {
Max { _item: PhantomData }
}
pub fn execute(&self, source: Observable<'a, Item>) -> Observable<'a, Item> {
Observable::<Item>::create(move |s| {
let result = Arc::new(RwLock::new(None::<Item>));
let sctl = StreamController::new(s);
let sctl_error = sctl.clone();
let sctl_complete = sctl.clone();
let result_next = Arc::clone(&result);
source.inner_subscribe(sctl.new_observer(
move |_, x| {
let mut r = result_next.write().unwrap();
if let Some(xx) = &*r {
if x > *xx {
*r = Some(x);
}
} else {
*r = Some(x);
}
},
move |_, e| {
sctl_error.sink_error(e);
},
move |serial| {
if let Some(x) = &*result.read().unwrap() {
sctl_complete.sink_next(x.clone());
}
sctl_complete.sink_complete(&serial);
},
));
})
}
}
impl<'a, Item> Observable<'a, Item>
where
Item: Clone + Send + Sync + PartialOrd,
{
pub fn max(&self) -> Observable<'a, Item> {
Max::new().execute(self.clone())
}
}
#[cfg(test)]
mod test {
use crate::prelude::*;
#[test]
fn basic() {
observables::from_iter([5, 6, 2, 7].into_iter())
.max()
.subscribe(
print_next_fmt!("{}"),
print_error!(),
print_complete!(),
);
}
#[test]
fn empty() {
observables::empty::<i32>().max().subscribe(
print_next_fmt!("{}"),
print_error!(),
print_complete!(),
);
}
#[test]
fn error() {
Observable::create(|s| {
s.next(1);
s.error(RxError::from_error("ERR!"))
})
.max()
.subscribe(
print_next_fmt!("{}"),
print_error_as!(&str),
print_complete!(),
);
}
}