rustlings/solutions/14_generics/generics3.rs
2024-07-12 18:31:23 +02:00

54 lines
1.4 KiB
Rust

// generics3.rs
// Execute `rustlings hint generics3` or use the `hint` watch subcommand for a hint.
// Here we added generic type `T` to function signature
// Now this function can be used with vector of any
fn into_dispose_nulls<T>(list: Vec<Option<T>>) -> Vec<T> {
list.into_iter().flatten().collect()
}
fn main() {
// You can optionally experiment here.
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn store_str_on_list() {
let names_list = vec![Some("maria"), Some("jacob"), None, Some("kacper"), None];
let only_values = into_dispose_nulls(names_list);
assert_eq!(only_values.len(), 3);
}
#[test]
fn store_numbers_on_list() {
let numbers_list = vec![Some(1), Some(2), None, Some(3)];
let only_values = into_dispose_nulls(numbers_list);
assert_eq!(only_values.len(), 3);
}
#[test]
fn store_custom_type_on_list() {
struct Rectangle {
width: i32,
height: i32,
}
impl Rectangle {
fn new(width: i32, height: i32) -> Self {
Self { width, height }
}
}
let custom_list = vec![
Some(Rectangle::new(1, 2)),
None,
None,
Some(Rectangle::new(3, 4)),
];
let only_values = into_dispose_nulls(custom_list);
assert_eq!(only_values.len(), 2);
}
}