Решение на упр.07 задача 1 от Божидар Виденов
Към профила на Божидар Виденов
Резултати
- 4 точки от тестове
- 0 бонус точки
- 4 точки общо
- 2 успешни тест(а)
- 0 неуспешни тест(а)
Код
struct Map<I, F, U>
where
I: Iterator,
F: Fn(I::Item) -> U,
{
map_fn: F,
items_iter: I,
}
fn iter_map<I, F, U>(iter: I, f: F) -> Map<I, F, U>
where
I: Iterator,
F: Fn(I::Item) -> U,
{
Map::<I, F, U> {
map_fn: f,
items_iter: iter,
}
}
impl<I, F, U> Iterator for Map<I, F, U>
where
I: Iterator,
F: Fn(I::Item) -> U,
{
type Item = U;
fn next(&mut self) -> Option<Self::Item> {
match self.items_iter.next() {
Some(value) => Some((self.map_fn)(value)),
None => None,
}
}
}
struct Filter<I, F>
where
I: Iterator,
F: Fn(&I::Item) -> bool,
{
filter_fn: F,
items_iter: I,
}
fn iter_filter<I, F>(iter: I, func: F) -> Filter<I, F>
where
I: Iterator,
F: Fn(&I::Item) -> bool,
{
Filter::<I, F> {
filter_fn: func,
items_iter: iter,
}
}
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> {
loop {
match self.items_iter.next() {
Some(value) => {
if !((self.filter_fn)(&value)) {
continue;
}
return Some(value);
}
None => {
return None;
}
}
}
}
}
//Не връщаме конкретния тип, защото ще много дълъг и неудобен за работа, защото типа ще трябва да
//се описва при всяко извикване на функцията
//В нашия случай типът ще е
// fn iter_filter_map<I, F, U, A, B>(iter: I, func: F) -> Map<Filter<Map<I, F, Option<U>>, A>, B, U>
// where
// I: Iterator,
// F: Fn(I::Item) -> Option<U>,
// A: Fn(&Option<U>) -> bool,
// B: Fn(Option<U>) -> U
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 filter_fn = |el: &Option<U>| el.is_some();
let map_fn = |el: Option<U>| el.unwrap();
iter_map(iter_filter(iter_map(iter, func), filter_fn), map_fn)
}
fn get_sum(text: &str) -> i32 {
iter_filter_map(text.split("\n"), |line| line.trim().parse::<i32>().ok()).sum()
}
#[derive(Debug, Eq, PartialEq)]
struct FoundWord<'a>(&'a str);
fn get_num_list(text: &str) -> Result<Vec<i32>, FoundWord<'_>> {
println!("{:?}", text);
iter_filter_map(text.split("\n"), |line: &str| -> Option<Result<i32, FoundWord<'_>>> {
let line = line.trim();
if line.is_empty() {
return None;
}
match line.parse::<i32>() {
Ok(num) => Some(Ok(num)),
Err(_) => Some(Err(FoundWord(line))),
}
})
.collect()
}
Лог от изпълнението
Updating crates.io index
Locking 17 packages to latest compatible versions
Compiling proc-macro2 v1.0.103
Compiling unicode-ident v1.0.22
Compiling quote v1.0.42
Compiling futures-core v0.3.31
Compiling futures-sink v0.3.31
Compiling futures-channel v0.3.31
Compiling pin-project-lite v0.2.16
Compiling futures-task v0.3.31
Compiling syn v2.0.111
Compiling futures-io v0.3.31
Compiling memchr v2.7.6
Compiling pin-utils v0.1.0
Compiling slab v0.4.11
Compiling solution v0.1.0 (/tmp/d20251127-1757769-1cp2fgz/solution)
warning: struct `Map` is never constructed
--> src/lib.rs:1:8
|
1 | struct Map<I, F, U>
| ^^^
|
= note: `#[warn(dead_code)]` on by default
warning: function `iter_map` is never used
--> src/lib.rs:10:4
|
10 | fn iter_map<I, F, U>(iter: I, f: F) -> Map<I, F, U>
| ^^^^^^^^
warning: struct `Filter` is never constructed
--> src/lib.rs:36:8
|
36 | struct Filter<I, F>
| ^^^^^^
warning: function `iter_filter` is never used
--> src/lib.rs:45:4
|
45 | fn iter_filter<I, F>(iter: I, func: F) -> Filter<I, F>
| ^^^^^^^^^^^
warning: function `iter_filter_map` is never used
--> src/lib.rs:90:4
|
90 | 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:102:4
|
102 | fn get_sum(text: &str) -> i32 {
| ^^^^^^^
warning: struct `FoundWord` is never constructed
--> src/lib.rs:107:8
|
107 | struct FoundWord<'a>(&'a str);
| ^^^^^^^^^
warning: function `get_num_list` is never used
--> src/lib.rs:109:4
|
109 | 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 8.53s
Running tests/solution_test.rs (target/debug/deps/solution_test-ee0783488e12dce9)
running 2 tests
test solution_test::test_adapters_ ... ok
test solution_test::test_text_parsers_ ... ok
test result: ok. 2 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s