Add option solutions

This commit is contained in:
David Bailey 2021-01-16 20:43:17 +00:00
parent 50c322d8c9
commit dd88abf3d8
2 changed files with 7 additions and 14 deletions
exercises/option

View file

@ -1,23 +1,19 @@
// 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 = [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);
} }
} }

View file

@ -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_value = Some(String::from("rustlings")); let optional_value = Some(String::from("rustlings"));
// TODO: Make this an if let statement whose value is "Some" type if let Some(value) = optional_value {
value = optional_value {
println!("the value of optional value is: {}", value); println!("the value of optional value is: {}", value);
} else { } else {
println!("The optional value doesn't contain anything!"); println!("The optional value doesn't contain anything!");
@ -19,7 +16,7 @@ fn main() {
// TODO: make this a while let statement - remember that vector.pop also adds another layer of Option<T> // TODO: make this a while let statement - remember that vector.pop also adds another layer of Option<T>
// You can stack `Option<T>`'s into while let and if let // You can stack `Option<T>`'s into while let and if let
value = optional_values_vec.pop() { while let Some(Some(value)) = optional_values_vec.pop() {
println!("current value: {}", value); println!("current value: {}", value);
} }
} }