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mod slice;
#[test]#[cfg(feature="alloc")]
fn test_slice() {
use crate::Cps;
use alloc::vec;
let mut foo = vec![1,2,3,4,5];
let update = |i| move |slice: &mut [i32]| {
let old_value = slice[0];
slice[0] = i;
old_value
};
assert!((&mut foo[..]).at(1..3).access(update(6)) == Some(2));
assert!(foo == vec![1,6,3,4,5]);
assert!((&mut foo[..]).at(2..).access(update(7)) == Some(3));
assert!(foo == vec![1,6,7,4,5]);
assert!((&mut foo[..]).at(..4).access(update(8)) == Some(1));
assert!(foo == vec![8,6,7,4,5]);
assert!((&mut foo[..]).at(..).access(update(9)) == Some(8));
assert!(foo == vec![9,6,7,4,5]);
assert!((&mut foo[..]).at(..=6).access(update(1)) == None);
assert!(foo == vec![9,6,7,4,5]);
assert!((&mut foo[..]).at(3..=4).access(update(0)) == Some(4));
assert!(foo == vec![9,6,7,0,5]);
assert!((&mut foo[..]).at(4).replace(1) == Some(5));
assert!(foo == vec![9,6,7,0,1]);
}
use crate::At;
impl<T> At<()> for Option<T> {
type View = T;
fn access_at<R, F>(&mut self, _: (), f: F) -> Option<R> where
F: FnOnce(&mut T) -> R
{
match self {
Some(x) => Some(f(x)),
None => None,
}
}
}
impl<T,S> At<()> for Result<T,S> {
type View = T;
fn access_at<R, F>(&mut self, _: (), f: F) -> Option<R> where
F: FnOnce(&mut T) -> R
{
match self {
Ok(x) => Some(f(x)),
Err(_) => None,
}
}
}
#[test]
fn test_optional() {
use crate::Cps;
let mut foo: Option<i32> = Some(0);
let mut bar: Option<i32> = None;
assert!(foo.at(()).replace(1) == Some(0));
assert!(foo == Some(1));
assert!(bar.at(()).replace(2) == None);
assert!(bar == None);
let mut foo: Result<i32,i32> = Ok(0);
let mut bar: Result<i32,i32> = Err(1);
assert!(foo.at(()).replace(1) == Some(0));
assert!(foo == Ok(1));
assert!(bar.at(()).replace(2) == None);
assert!(bar == Err(1));
}