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Option3
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@ -1,8 +1,6 @@
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// options1.rs
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// Execute `rustlings hint options1` or use the `hint` watch subcommand for a hint.
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// I AM NOT DONE
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// This function returns how much icecream there is left in the fridge.
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// If it's before 10PM, there's 5 pieces left. At 10PM, someone eats them
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// all, so there'll be no more left :(
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@ -10,7 +8,13 @@ fn maybe_icecream(time_of_day: u16) -> Option<u16> {
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// We use the 24-hour system here, so 10PM is a value of 22 and 12AM is a value of 0
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// The Option output should gracefully handle cases where time_of_day > 23.
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// TODO: Complete the function body - remember to return an Option!
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???
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if time_of_day > 24 || time_of_day < 0 {
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return None;
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}
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if time_of_day >= 22 {
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return Some(0);
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}
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Some(5)
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}
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#[cfg(test)]
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@ -30,6 +34,6 @@ mod tests {
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fn raw_value() {
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// TODO: Fix this test. How do you get at the value contained in the Option?
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let icecreams = maybe_icecream(12);
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assert_eq!(icecreams, 5);
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assert_eq!(icecreams, Some(5));
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}
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}
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@ -1,7 +1,6 @@
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// options2.rs
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// Execute `rustlings hint options2` or use the `hint` watch subcommand for a hint.
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// I AM NOT DONE
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#[cfg(test)]
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mod tests {
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@ -13,7 +12,7 @@ mod tests {
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let optional_target = Some(target);
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// TODO: Make this an if let statement whose value is "Some" type
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word = optional_target {
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if let Some(word) = optional_target {
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assert_eq!(word, target);
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}
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}
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@ -28,7 +27,7 @@ mod tests {
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// TODO: make this a while let statement - remember that vector.pop also adds another layer of Option<T>
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// You can stack `Option<T>`'s into while let and if let
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integer = optional_integers.pop() {
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while let Some(Some(integer)) = optional_integers.pop() {
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assert_eq!(integer, range);
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range -= 1;
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}
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@ -11,7 +11,7 @@ struct Point {
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fn main() {
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let y: Option<Point> = Some(Point { x: 100, y: 200 });
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match y {
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match &y {
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Some(p) => println!("Co-ordinates are {},{} ", p.x, p.y),
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_ => println!("no match"),
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}
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