Решение на упр.07 задача 1 от Георги Илиев
Резултати
- 4 точки от тестове
- 0 бонус точки
- 4 точки общо
- 3 успешни тест(а)
- 0 неуспешни тест(а)
Код
struct Map<I, F> {
iter: I,
f: F,
}
fn iter_map<I, F, U>(iter: I, f: F) -> Map<I, F>
where
I: Iterator,
F: Fn(I::Item) -> U,
{
Map { iter, f }
}
impl<I, F, U> Iterator for Map<I, F>
where
I: Iterator,
F: Fn(I::Item) -> U,
{
type Item = U;
fn next(&mut self) -> Option<Self::Item> {
self.iter.next().map(|item| (self.f)(item))
}
}
struct Filter<I, F> {
iter: I,
func: F,
}
fn iter_filter<I, F>(iter: I, func: F) -> Filter<I, F>
where
I: Iterator,
F: Fn(&I::Item) -> bool,
{
Filter { iter, func }
}
impl<I, F> Iterator for Filter<I, F>
where
I: Iterator,
F: Fn(&I::Item) -> bool,
{
type Item = I::Item;
fn next(&mut self) -> Option<Self::Item> {
while let Some(item) = self.iter.next() {
if (self.func)(&item) {
return Some(item);
}
}
None
}
}
// Връщаме Iterator за да скрием вложените типове. Тъй като използваме
// iter_map -> iter_filter -> отново iter_map, типът е
// Map<Filter<Map<I, F>, fn -> bool>, fn -> bool>
fn iter_filter_map<I, F, U>(iter: I, func: F) -> impl Iterator<Item = U>
where
I: Iterator,
F: Fn(I::Item) -> Option<U>,
{
let apply_func = iter_map(iter, func);
let filtered = iter_filter(apply_func, |x: &Option<U>| x.is_some());
iter_map(filtered, |x: Option<U>| x.unwrap())
}
fn get_sum(text: &str) -> i32 {
text.lines()
.map(str::trim)
.filter_map(|line| line.parse::<i32>().ok())
.sum()
}
#[test]
fn test_adapters() {
let iter = iter_filter(0..10, |&x| x % 2 == 0);
assert_eq!(iter.collect::<Vec<i32>>(), vec![0, 2, 4, 6, 8]);
let iter = iter_map(5..10, |x| x * x);
assert_eq!(iter.collect::<Vec<i32>>(), vec![25, 36, 49, 64, 81]);
let iter = iter_filter_map(0..10, |x| if x % 2 == 0 { Some(x * x) } else { None });
assert_eq!(iter.collect::<Vec<i32>>(), vec![0, 4, 16, 36, 64]);
}
#[derive(Debug, Eq, PartialEq)]
struct FoundWord<'a>(&'a str);
fn get_num_list(text: &str) -> Result<Vec<i32>, FoundWord<'_>> {
text.lines()
.map(str::trim)
.filter(|line| !line.is_empty())
.map(|line| {
match line.parse::<i32>() {
Ok(n) => Ok(n),
Err(_) => Err(FoundWord(line)),
}
})
.collect::<Result<Vec<i32>, FoundWord>>()
}
Лог от изпълнението
Updating crates.io index
Locking 17 packages to latest compatible versions
Compiling proc-macro2 v1.0.103
Compiling quote v1.0.42
Compiling unicode-ident v1.0.22
Compiling futures-sink v0.3.31
Compiling futures-core v0.3.31
Compiling futures-channel v0.3.31
Compiling memchr v2.7.6
Compiling syn v2.0.111
Compiling pin-utils v0.1.0
Compiling slab v0.4.11
Compiling futures-io v0.3.31
Compiling futures-task v0.3.31
Compiling pin-project-lite v0.2.16
Compiling solution v0.1.0 (/tmp/d20251127-1757769-dgco8j/solution)
warning: struct `Map` is never constructed
--> src/lib.rs:1:8
|
1 | struct Map<I, F> {
| ^^^
|
= note: `#[warn(dead_code)]` on by default
warning: function `iter_map` is never used
--> src/lib.rs:6:4
|
6 | fn iter_map<I, F, U>(iter: I, f: F) -> Map<I, F>
| ^^^^^^^^
warning: struct `Filter` is never constructed
--> src/lib.rs:26:8
|
26 | struct Filter<I, F> {
| ^^^^^^
warning: function `iter_filter` is never used
--> src/lib.rs:31:4
|
31 | fn iter_filter<I, F>(iter: I, func: F) -> Filter<I, F>
| ^^^^^^^^^^^
warning: function `iter_filter_map` is never used
--> src/lib.rs:59:4
|
59 | fn iter_filter_map<I, F, U>(iter: I, func: F) -> impl Iterator<Item = U>
| ^^^^^^^^^^^^^^^
warning: function `get_sum` is never used
--> src/lib.rs:70:4
|
70 | fn get_sum(text: &str) -> i32 {
| ^^^^^^^
warning: struct `FoundWord` is never constructed
--> src/lib.rs:90:8
|
90 | struct FoundWord<'a>(&'a str);
| ^^^^^^^^^
warning: function `get_num_list` is never used
--> src/lib.rs:92:4
|
92 | fn get_num_list(text: &str) -> Result<Vec<i32>, FoundWord<'_>> {
| ^^^^^^^^^^^^
warning: `solution` (lib) generated 8 warnings
Compiling futures-macro v0.3.31
Compiling futures-util v0.3.31
Compiling futures-executor v0.3.31
Compiling futures v0.3.31
Finished `test` profile [unoptimized + debuginfo] target(s) in 8.67s
Running tests/solution_test.rs (target/debug/deps/solution_test-ee0783488e12dce9)
running 3 tests
test solution_test::test_adapters ... ok
test solution_test::test_adapters_ ... ok
test solution_test::test_text_parsers_ ... ok
test result: ok. 3 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s