Complete option exercises ()

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Tyler Cardinal 2021-05-13 21:40:20 -05:00 committed by GitHub
parent 64d73890dc
commit 10dabcd66c
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2 changed files with 6 additions and 13 deletions
exercises/option

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@ -1,23 +1,21 @@
// option1.rs // option1.rs
// Make me compile! Execute `rustlings hint option1` for hints // Make me compile! Execute `rustlings hint option1` for hints
// I AM NOT DONE
// you can modify anything EXCEPT for this function's sig // you can modify anything EXCEPT for this function's sig
fn print_number(maybe_number: Option<u16>) { fn print_number(maybe_number: Option<u16>) {
println!("printing: {}", maybe_number.unwrap()); println!("printing: {}", maybe_number.unwrap());
} }
fn main() { fn main() {
print_number(13); print_number(Some(13));
print_number(99); print_number(Some(99));
let mut numbers: [Option<u16>; 5]; let mut numbers: [Option<u16>; 5] = [None; 5];
for iter in 0..5 { for iter in 0..5 {
let number_to_add: u16 = { let number_to_add: u16 = {
((iter * 1235) + 2) / (4 * 16) ((iter * 1235) + 2) / (4 * 16)
}; };
numbers[iter as usize] = number_to_add; numbers[iter as usize] = Some(number_to_add);
} }
} }

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@ -1,12 +1,9 @@
// option2.rs // option2.rs
// Make me compile! Execute `rustlings hint option2` for hints // Make me compile! Execute `rustlings hint option2` for hints
// I AM NOT DONE
fn main() { fn main() {
let optional_word = Some(String::from("rustlings")); let optional_word = Some(String::from("rustlings"));
// TODO: Make this an if let statement whose value is "Some" type if let Some(word) = optional_word {
word = optional_word {
println!("The word is: {}", word); println!("The word is: {}", word);
} else { } else {
println!("The optional word doesn't contain anything"); println!("The optional word doesn't contain anything");
@ -17,9 +14,7 @@ fn main() {
optional_integers_vec.push(Some(x)); optional_integers_vec.push(Some(x));
} }
// TODO: make this a while let statement - remember that vector.pop also adds another layer of Option<T> while let Some(Some(integer)) = optional_integers_vec.pop() {
// You can stack `Option<T>`'s into while let and if let
integer = optional_integers_vec.pop() {
println!("current value: {}", integer); println!("current value: {}", integer);
} }
} }