traits done

exercises/generics/generics2.rs

@@ -3,14 +3,12 @@
 
 // Execute `rustlings hint generics2` for hints!
 
-// I AM NOT DONE
-
-struct Wrapper {
-    value: u32,
+struct Wrapper<T> {
+    value: T,
 }
 
-impl Wrapper {
-    pub fn new(value: u32) -> Self {
+impl<T> Wrapper<T> {
+    pub fn new(value: T) -> Self {
         Wrapper { value }
     }
 }

exercises/generics/generics3.rs

@@ -10,18 +10,20 @@
 
 // Execute 'rustlings hint generics3' for hints!
 
-// I AM NOT DONE
+use std::fmt::Display;
 
-pub struct ReportCard {
-    pub grade: f32,
+pub struct ReportCard<T: Display> {
+    pub grade: T,
     pub student_name: String,
     pub student_age: u8,
 }
 
-impl ReportCard {
-    pub fn print(&self) -> String {
-        format!("{} ({}) - achieved a grade of {}",
-            &self.student_name, &self.student_age, &self.grade)
+impl<T: Display> ReportCard<T> {
+    fn print(&self) -> String {
+        format!(
+            "{} ({}) - achieved a grade of {}",
+            &self.student_name, &self.student_age, &self.grade
+        )
     }
 }
 
@@ -46,7 +48,7 @@ mod tests {
     fn generate_alphabetic_report_card() {
         // TODO: Make sure to change the grade here after you finish the exercise.
         let report_card = ReportCard {
-            grade: 2.1,
+            grade: "A+".to_string(),
             student_name: "Gary Plotter".to_string(),
             student_age: 11,
         };

exercises/option/option1.rs

@@ -1,23 +1,19 @@
 // option1.rs
 // Make me compile! Execute `rustlings hint option1` for hints
 
-// I AM NOT DONE
-
 // you can modify anything EXCEPT for this function's signature
 fn print_number(maybe_number: Option<u16>) {
     println!("printing: {}", maybe_number.unwrap());
 }
 
 fn main() {
-    print_number(13);
-    print_number(99);
+    print_number(Some(13));
+    print_number(Some(99));
 
-    let mut numbers: [Option<u16>; 5];
+    let mut numbers: [Option<u16>; 5] = [Some(0); 5];
     for iter in 0..5 {
-        let number_to_add: u16 = {
-            ((iter * 1235) + 2) / (4 * 16)
-        };
+        let number_to_add: u16 = { ((iter * 1235) + 2) / (4 * 16) };
 
-        numbers[iter as usize] = number_to_add;
+        numbers[iter as usize] = Some(number_to_add);
     }
 }

exercises/option/option2.rs

@@ -1,13 +1,11 @@
 // option2.rs
 // Make me compile! Execute `rustlings hint option2` for hints
 
-// I AM NOT DONE
-
 fn main() {
     let optional_word = Some(String::from("rustlings"));
     // TODO: Make this an if let statement whose value is "Some" type
-    word = optional_word {
-        println!("The word is: {}", word);
+    if let word = optional_word {
+        println!("The word is: {:?}", word);
     } else {
         println!("The optional word doesn't contain anything");
     }
@@ -19,7 +17,7 @@ fn main() {
 
     // 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
-    integer = optional_integers_vec.pop() {
-        println!("current value: {}", integer);
+    while let Some(integer) = optional_integers_vec.pop() {
+        println!("current value: {:?}", integer);
     }
 }

exercises/option/option3.rs

@@ -1,8 +1,6 @@
 // option3.rs
 // Make me compile! Execute `rustlings hint option3` for hints
 
-// I AM NOT DONE
-
 struct Point {
     x: i32,
     y: i32,
@@ -12,7 +10,7 @@ fn main() {
     let y: Option<Point> = Some(Point { x: 100, y: 200 });
 
     match y {
-        Some(p) => println!("Co-ordinates are {},{} ", p.x, p.y),
+        Some(ref p) => println!("Co-ordinates are {},{} ", p.x, p.y),
         _ => println!("no match"),
     }
     y; // Fix without deleting this line.

exercises/traits/traits1.rs

@@ -8,14 +8,17 @@
 // which appends "Bar" to any object
 // implementing this trait.
 
-// I AM NOT DONE
-
 trait AppendBar {
     fn append_bar(self) -> Self;
 }
 
 impl AppendBar for String {
     //Add your code here
+    fn append_bar(self) -> String {
+        let mut out = String::from(&self);
+        out.push_str("Bar");
+        out.to_string()
+    }
 }
 
 fn main() {

exercises/traits/traits2.rs

@@ -17,6 +17,12 @@ trait AppendBar {
 }
 
 //TODO: Add your code here
+impl AppendBar for Vec<String> {
+    fn append_bar(mut self) -> Vec<String> {
+        self.append(&mut vec!["Bar".to_string()]);
+        self
+    }
+}
 
 #[cfg(test)]
 mod tests {