update

exercises/error_handling/errors1.rs

@@ -9,14 +9,14 @@
 // Execute `rustlings hint errors1` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
-pub fn generate_nametag_text(name: String) -> Option<String> {
+
+pub fn generate_nametag_text(name: String) -> Result<String, String> {
     if name.is_empty() {
         // Empty names aren't allowed.
-        None
+        Err("`name` was empty; it must be nonempty.".into())
     } else {
-        Some(format!("Hi! My name is {}", name))
+        Ok(format!("Hi! My name is {}", name))
     }
 }
 

exercises/error_handling/errors2.rs

@@ -19,16 +19,23 @@
 // Execute `rustlings hint errors2` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
+
 
 use std::num::ParseIntError;
 
 pub fn total_cost(item_quantity: &str) -> Result<i32, ParseIntError> {
     let processing_fee = 1;
     let cost_per_item = 5;
     let qty = item_quantity.parse::<i32>();
-
-    Ok(qty * cost_per_item + processing_fee)
+    match qty {
+        Ok(value) => {
+            Ok(value * cost_per_item + processing_fee)
+        }
+        Err(err) => {
+            Err(err)
+        }
+    }
+
 }
 
 #[cfg(test)]

exercises/error_handling/errors3.rs

@@ -7,15 +7,15 @@
 // Execute `rustlings hint errors3` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
+
 
 use std::num::ParseIntError;
 
 fn main() {
     let mut tokens = 100;
     let pretend_user_input = "8";
 
-    let cost = total_cost(pretend_user_input)?;
+    let cost = total_cost(pretend_user_input).unwrap();
 
     if cost > tokens {
         println!("You can't afford that many!");
@@ -28,7 +28,7 @@ fn main() {
 pub fn total_cost(item_quantity: &str) -> Result<i32, ParseIntError> {
     let processing_fee = 1;
     let cost_per_item = 5;
-    let qty = item_quantity.parse::<i32>()?;
+    let qty = item_quantity.parse::<i32>().unwrap();
 
     Ok(qty * cost_per_item + processing_fee)
 }

exercises/error_handling/errors4.rs

@@ -3,7 +3,7 @@
 // Execute `rustlings hint errors4` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
+
 
 #[derive(PartialEq, Debug)]
 struct PositiveNonzeroInteger(u64);
@@ -17,7 +17,14 @@ enum CreationError {
 impl PositiveNonzeroInteger {
     fn new(value: i64) -> Result<PositiveNonzeroInteger, CreationError> {
         // Hmm...? Why is this only returning an Ok value?
-        Ok(PositiveNonzeroInteger(value as u64))
+        if value > 0 {
+            Ok(PositiveNonzeroInteger(value as u64))
+        } else if value < 0 {
+            Err(CreationError::Negative)
+        } else {
+            Err(CreationError::Zero)
+        }
+
     }
 }
 

exercises/error_handling/errors5.rs

@@ -22,14 +22,15 @@
 // Execute `rustlings hint errors5` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
+
 
 use std::error;
 use std::fmt;
 use std::num::ParseIntError;
+use std::error::Error;
 
 // TODO: update the return type of `main()` to make this compile.
-fn main() -> Result<(), Box<dyn ???>> {
+fn main() -> Result<(), Box<dyn Error>> {
     let pretend_user_input = "42";
     let x: i64 = pretend_user_input.parse()?;
     println!("output={:?}", PositiveNonzeroInteger::new(x)?);

exercises/error_handling/errors6.rs

@@ -9,7 +9,7 @@
 // Execute `rustlings hint errors6` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
+
 
 use std::num::ParseIntError;
 
@@ -26,12 +26,15 @@ impl ParsePosNonzeroError {
     }
     // TODO: add another error conversion function here.
     // fn from_parseint...
+    fn from_parseint(err: ParseIntError) -> ParsePosNonzeroError {
+        ParsePosNonzeroError::ParseInt(err)
+    }
 }
 
 fn parse_pos_nonzero(s: &str) -> Result<PositiveNonzeroInteger, ParsePosNonzeroError> {
     // TODO: change this to return an appropriate error instead of panicking
     // when `parse()` returns an error.
-    let x: i64 = s.parse().unwrap();
+    let x: i64 = s.parse().map_err(ParsePosNonzeroError::from_parseint)?;
     PositiveNonzeroInteger::new(x).map_err(ParsePosNonzeroError::from_creation)
 }
 

exercises/generics/generics1.rs

@@ -6,9 +6,9 @@
 // Execute `rustlings hint generics1` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
+
 
 fn main() {
-    let mut shopping_list: Vec<?> = Vec::new();
+    let mut shopping_list: Vec<&str> = Vec::new();
     shopping_list.push("milk");
 }

exercises/generics/generics2.rs

@@ -6,14 +6,14 @@
 // Execute `rustlings hint generics2` or use the `hint` watch subcommand for a
 // hint.
 
-// 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/traits/traits1.rs

@@ -7,14 +7,17 @@
 // Execute `rustlings hint traits1` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
+
 
 trait AppendBar {
     fn append_bar(self) -> Self;
 }
 
 impl AppendBar for String {
     // TODO: Implement `AppendBar` for type `String`.
+    fn append_bar(self) -> Self {
+        self + "Bar"
+    }
 }
 
 fn main() {

exercises/traits/traits2.rs

@@ -8,14 +8,21 @@
 //
 // Execute `rustlings hint traits2` or use the `hint` watch subcommand for a hint.
 
-// I AM NOT DONE
+
 
 trait AppendBar {
     fn append_bar(self) -> Self;
 }
 
 // TODO: Implement trait `AppendBar` for a vector of strings.
 
+impl AppendBar for Vec<String> {
+    fn append_bar(mut self) -> Self{
+        self.push("Bar".to_string());
+        self
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;

exercises/traits/traits3.rs

@@ -8,7 +8,7 @@
 // Execute `rustlings hint traits3` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
+
 
 pub trait Licensed {
     fn licensing_info(&self) -> String;
@@ -22,8 +22,16 @@ struct OtherSoftware {
     version_number: String,
 }
 
-impl Licensed for SomeSoftware {} // Don't edit this line
-impl Licensed for OtherSoftware {} // Don't edit this line
+impl Licensed for SomeSoftware {
+    fn licensing_info(&self) -> String{
+        "Some information".to_string()
+    }
+} // Don't edit this line
+impl Licensed for OtherSoftware {
+    fn licensing_info(&self) -> String{
+        "Some information".to_string()
+    }
+} // Don't edit this line
 
 #[cfg(test)]
 mod tests {

exercises/traits/traits4.rs

@@ -7,7 +7,7 @@
 // Execute `rustlings hint traits4` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
+
 
 pub trait Licensed {
     fn licensing_info(&self) -> String {
@@ -23,7 +23,7 @@ impl Licensed for SomeSoftware {}
 impl Licensed for OtherSoftware {}
 
 // YOU MAY ONLY CHANGE THE NEXT LINE
-fn compare_license_types(software: ??, software_two: ??) -> bool {
+fn compare_license_types<T: Licensed, U: Licensed>(software: T , software_two: U) -> bool {
     software.licensing_info() == software_two.licensing_info()
 }
 

exercises/traits/traits5.rs

@@ -7,7 +7,6 @@
 // Execute `rustlings hint traits5` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 pub trait SomeTrait {
     fn some_function(&self) -> bool {
@@ -30,7 +29,7 @@ impl SomeTrait for OtherStruct {}
 impl OtherTrait for OtherStruct {}
 
 // YOU MAY ONLY CHANGE THE NEXT LINE
-fn some_func(item: ??) -> bool {
+fn some_func<T: SomeTrait + OtherTrait>(item: T) -> bool {
     item.some_function() && item.other_function()
 }