quiz2: Use repeat

Update iterator solution in quiz2.rs

README.md

@@ -19,7 +19,7 @@ It contains code examples and exercises similar to Rustlings, but online.
 
 Before installing Rustlings, you need to have _Rust installed_.
 Visit [www.rust-lang.org/tools/install](https://www.rust-lang.org/tools/install) for further instructions on installing Rust.
-This'll also install _Cargo_, Rust's package/project manager.
+This will also install _Cargo_, Rust's package/project manager.
 
 > 🐧 If you're on Linux, make sure you've installed `gcc` (for a linker).
 >
@@ -124,7 +124,7 @@ Continue practicing your Rust skills by building your own projects, contributing
 
 Do you want to create your own set of Rustlings exercises to focus on some specific topic?
 Or do you want to translate the original Rustlings exercises?
-Then follow the link to the guide about [third-party exercises](THIRD_PARTY_EXERCISES.md)!
+Then follow the link to the guide about [third-party exercises](https://github.com/rust-lang/rustlings/blob/main/THIRD_PARTY_EXERCISES.md)!
 
 ## Uninstalling Rustlings
 

dev/rustlings-repo.txt

@@ -1 +1 @@
-This file is used to check if the user tries to run Rustlings in the repository (the method before v6)
+This file is used to check if the user tries to run Rustlings in the repository (the method before version 6)

exercises/08_enums/enums3.rs

@@ -12,6 +12,7 @@ struct State {
     height: u64,
     position: Point,
     message: String,
+    // RGB color composed of red, green and blue.
     color: (u8, u8, u8),
     quit: bool,
 }
@@ -30,8 +31,8 @@ impl State {
         self.message = s;
     }
 
-    fn change_color(&mut self, color: (u8, u8, u8)) {
-        self.color = color;
+    fn change_color(&mut self, red: u8, green: u8, blue: u8) {
+        self.color = (red, green, blue);
     }
 
     fn quit(&mut self) {
@@ -39,9 +40,8 @@ impl State {
     }
 
     fn process(&mut self, message: Message) {
-        // TODO: Create a match expression to process the different message variants.
-        // Remember: When passing a tuple as a function argument, you'll need extra parentheses:
-        // e.g. `foo((t, u, p, l, e))`
+        // TODO: Create a match expression to process the different message
+        // variants using the methods defined above.
     }
 }
 

exercises/19_smart_pointers/cow1.rs

@@ -45,8 +45,9 @@ mod tests {
     #[test]
     fn owned_no_mutation() {
         // We can also pass `vec` without `&` so `Cow` owns it directly. In this
-        // case, no mutation occurs and thus also no clone. But the result is
-        // still owned because it was never borrowed or mutated.
+        // case, no mutation occurs (all numbers are already absolute) and thus
+        // also no clone. But the result is still owned because it was never
+        // borrowed or mutated.
         let vec = vec![0, 1, 2];
         let mut input = Cow::from(vec);
         abs_all(&mut input);
@@ -56,9 +57,9 @@ mod tests {
 
     #[test]
     fn owned_mutation() {
-        // Of course this is also the case if a mutation does occur. In this
-        // case, the call to `to_mut()` in the `abs_all` function returns a
-        // reference to the same data as before.
+        // Of course this is also the case if a mutation does occur (not all
+        // numbers are absolute). In this case, the call to `to_mut()` in the
+        // `abs_all` function returns a reference to the same data as before.
         let vec = vec![-1, 0, 1];
         let mut input = Cow::from(vec);
         abs_all(&mut input);

solutions/08_enums/enums3.rs

@@ -34,8 +34,8 @@ impl State {
         self.message = s;
     }
 
-    fn change_color(&mut self, color: (u8, u8, u8)) {
-        self.color = color;
+    fn change_color(&mut self, red: u8, green: u8, blue: u8) {
+        self.color = (red, green, blue);
     }
 
     fn quit(&mut self) {
@@ -47,7 +47,7 @@ impl State {
             Message::Resize { width, height } => self.resize(width, height),
             Message::Move(point) => self.move_position(point),
             Message::Echo(s) => self.echo(s),
-            Message::ChangeColor(r, g, b) => self.change_color((r, g, b)),
+            Message::ChangeColor(r, g, b) => self.change_color(r, g, b),
             Message::Quit => self.quit(),
         }
     }

solutions/19_smart_pointers/cow1.rs

@@ -45,8 +45,9 @@ mod tests {
     #[test]
     fn owned_no_mutation() {
         // We can also pass `vec` without `&` so `Cow` owns it directly. In this
-        // case, no mutation occurs and thus also no clone. But the result is
-        // still owned because it was never borrowed or mutated.
+        // case, no mutation occurs (all numbers are already absolute) and thus
+        // also no clone. But the result is still owned because it was never
+        // borrowed or mutated.
         let vec = vec![0, 1, 2];
         let mut input = Cow::from(vec);
         abs_all(&mut input);
@@ -56,9 +57,9 @@ mod tests {
 
     #[test]
     fn owned_mutation() {
-        // Of course this is also the case if a mutation does occur. In this
-        // case, the call to `to_mut()` in the `abs_all` function returns a
-        // reference to the same data as before.
+        // Of course this is also the case if a mutation does occur (not all
+        // numbers are absolute). In this case, the call to `to_mut()` in the
+        // `abs_all` function returns a reference to the same data as before.
         let vec = vec![-1, 0, 1];
         let mut input = Cow::from(vec);
         abs_all(&mut input);

solutions/quizzes/quiz2.rs

@@ -24,17 +24,12 @@ mod my_module {
     pub fn transformer(input: Vec<(String, Command)>) -> Vec<String> {
         let mut output = Vec::new();
 
-        for (mut string, command) in input {
+        for (string, command) in input {
             // Create the new string.
             let new_string = match command {
                 Command::Uppercase => string.to_uppercase(),
                 Command::Trim => string.trim().to_string(),
-                Command::Append(n) => {
-                    for _ in 0..n {
-                        string += "bar";
-                    }
-                    string
-                }
+                Command::Append(n) => string + &"bar".repeat(n),
             };
 
             // Push the new string to the output vector.
@@ -49,15 +44,10 @@ mod my_module {
     pub fn transformer_iter(input: Vec<(String, Command)>) -> Vec<String> {
         input
             .into_iter()
-            .map(|(mut string, command)| match command {
+            .map(|(string, command)| match command {
                 Command::Uppercase => string.to_uppercase(),
                 Command::Trim => string.trim().to_string(),
-                Command::Append(n) => {
-                    for _ in 0..n {
-                        string += "bar";
-                    }
-                    string
-                }
+                Command::Append(n) => string + &"bar".repeat(n),
             })
             .collect()
     }

src/app_state.rs

@@ -403,6 +403,9 @@ impl AppState {
             writeln!(writer, "{}", "ok".green())?;
         }
 
+        // Write that the last exercise is done.
+        self.write()?;
+
         clear_terminal(writer)?;
         writer.write_all(FENISH_LINE.as_bytes())?;
 

src/dev/new.rs

@@ -139,7 +139,7 @@ const README: &str = "# Rustlings 🦀
 
 Welcome to these third-party Rustlings exercises 😃
 
-First, [install Rustlings using the official instructions in the README of the Rustlings project](https://github.com/rust-lang/rustlings) ✅
+First, [install Rustlings using the official instructions](https://github.com/rust-lang/rustlings) ✅
 
-Then, open your terminal in this directory and run `rustlings` to get started with the exercises 🚀
+Then, clone this repository, open a terminal in this directory and run `rustlings` to get started with the exercises 🚀
 ";

src/main.rs

@@ -197,9 +197,10 @@ fn main() -> Result<()> {
     Ok(())
 }
 
-const OLD_METHOD_ERR: &str = "You are trying to run Rustlings using the old method before v6.
+const OLD_METHOD_ERR: &str =
+    "You are trying to run Rustlings using the old method before version 6.
 The new method doesn't include cloning the Rustlings' repository.
-Please follow the instructions in the README:
+Please follow the instructions in `README.md`:
 https://github.com/rust-lang/rustlings#getting-started";
 
 const FORMAT_VERSION_HIGHER_ERR: &str =
@@ -216,5 +217,5 @@ const PRE_INIT_MSG: &str = r"
  |_|   \__,_|___/\__|_|_|_| |_|\__, |___/
                                |___/
 
-The `exercises` directory wasn't found in the current directory.
+The `exercises/` directory couldn't be found in the current directory.
 If you are just starting with Rustlings, run the command `rustlings init` to initialize it.";