Merge 59e8f70e55 into e6cb104294

exercises/22_clippy/clippy3.rs

@@ -4,11 +4,9 @@
 #[rustfmt::skip]
 #[allow(unused_variables, unused_assignments)]
 fn main() {
-    let my_option: Option<&str> = None;
-    // Assume that you don't know the value of `my_option`.
-    // In the case of `Some`, we want to print its value.
+    let my_option: Option<()> = None;
     if my_option.is_none() {
-        println!("{}", my_option.unwrap());
+        println!("{:?}", my_option.unwrap());
     }
 
     let my_arr = &[

solutions/13_error_handling/errors6.rs

@@ -29,21 +29,6 @@ impl ParsePosNonzeroError {
     }
 }
 
-// As an alternative solution, implementing the `From` trait allows for the
-// automatic conversion from a `ParseIntError` into a `ParsePosNonzeroError`
-// using the `?` operator, without the need to call `map_err`.
-//
-// ```
-// let x: i64 = s.parse()?;
-// ```
-//
-// Traits like `From` will be dealt with in later exercises.
-impl From<ParseIntError> for ParsePosNonzeroError {
-    fn from(err: ParseIntError) -> Self {
-        ParsePosNonzeroError::ParseInt(err)
-    }
-}
-
 #[derive(PartialEq, Debug)]
 struct PositiveNonzeroInteger(u64);
 

solutions/22_clippy/clippy3.rs

@@ -3,11 +3,11 @@ use std::mem;
 #[rustfmt::skip]
 #[allow(unused_variables, unused_assignments)]
 fn main() {
-    let my_option: Option<&str> = None;
+    let my_option: Option<()> = None;
     // `unwrap` of an `Option` after checking if it is `None` will panic.
     // Use `if-let` instead.
     if let Some(value) = my_option {
-        println!("{value}");
+        println!("{value:?}");
     }
 
     // A comma was missing.