Antonio Scandurra
901525bf77
This required passing a `Context` object to `Summary` and introducing a new `SeekDimension` trait that allows comparing two dimensions and pass an additional context object.
71 lines
1.9 KiB
Rust
71 lines
1.9 KiB
Rust
use rand::prelude::*;
|
|
use std::cmp::Ordering;
|
|
|
|
pub fn post_inc(value: &mut usize) -> usize {
|
|
let prev = *value;
|
|
*value += 1;
|
|
prev
|
|
}
|
|
|
|
/// Extend a sorted vector with a sorted sequence of items, maintaining the vector's sort order and
|
|
/// enforcing a maximum length. Sort the items according to the given callback. Before calling this,
|
|
/// both `vec` and `new_items` should already be sorted according to the `cmp` comparator.
|
|
pub fn extend_sorted<T, I, F>(vec: &mut Vec<T>, new_items: I, limit: usize, mut cmp: F)
|
|
where
|
|
I: IntoIterator<Item = T>,
|
|
F: FnMut(&T, &T) -> Ordering,
|
|
{
|
|
let mut start_index = 0;
|
|
for new_item in new_items {
|
|
if let Err(i) = vec[start_index..].binary_search_by(|m| cmp(m, &new_item)) {
|
|
let index = start_index + i;
|
|
if vec.len() < limit {
|
|
vec.insert(index, new_item);
|
|
} else if index < vec.len() {
|
|
vec.pop();
|
|
vec.insert(index, new_item);
|
|
}
|
|
start_index = index;
|
|
}
|
|
}
|
|
}
|
|
|
|
pub struct RandomCharIter<T: Rng>(T);
|
|
|
|
impl<T: Rng> RandomCharIter<T> {
|
|
pub fn new(rng: T) -> Self {
|
|
Self(rng)
|
|
}
|
|
}
|
|
|
|
impl<T: Rng> Iterator for RandomCharIter<T> {
|
|
type Item = char;
|
|
|
|
fn next(&mut self) -> Option<Self::Item> {
|
|
if self.0.gen_bool(1.0 / 5.0) {
|
|
Some('\n')
|
|
} else {
|
|
Some(self.0.gen_range(b'a'..b'z' + 1).into())
|
|
}
|
|
}
|
|
}
|
|
|
|
#[cfg(test)]
|
|
mod tests {
|
|
use super::*;
|
|
|
|
#[test]
|
|
fn test_extend_sorted() {
|
|
let mut vec = vec![];
|
|
|
|
extend_sorted(&mut vec, vec![21, 17, 13, 8, 1, 0], 5, |a, b| b.cmp(a));
|
|
assert_eq!(vec, &[21, 17, 13, 8, 1]);
|
|
|
|
extend_sorted(&mut vec, vec![101, 19, 17, 8, 2], 8, |a, b| b.cmp(a));
|
|
assert_eq!(vec, &[101, 21, 19, 17, 13, 8, 2, 1]);
|
|
|
|
extend_sorted(&mut vec, vec![1000, 19, 17, 9, 5], 8, |a, b| b.cmp(a));
|
|
assert_eq!(vec, &[1000, 101, 21, 19, 17, 13, 9, 8]);
|
|
}
|
|
}
|