Updates per review comments

Author: frank-at-adacore

courses/rust_essentials/200_error_handling/03-result.rst

@@ -41,11 +41,52 @@ Handling Results
 
 :error:`Failed to open: No such file or directory (os error 2)`
 
-* Helper methods
+----------------
+Helper Methods
+----------------
 
-  * :rust:`.unwrap()` - returns the value or panics
-  * :rust:`.expect("Msg")` - like :rust:`unwrap`, with custom panic message
-  * :rust:`.unwrap_or(default)` - fallback value on error
+.. code:: rust
+
+  let good: Result<i32, &str> = Ok(42);
+  let bad: Result<i32, &str> = Err("Problem");
+
+* :rust:`.unwrap()` - returns the value or panics
+
+  .. code:: rust
+
+    println!("Good: {}", good.unwrap());
+    println!("Bad: {}", bad.unwrap());
+
+  .. code:: output
+
+    Good: 42
+    thread 'main' panicked at src\main.rs:5:27:
+    called `Result::unwrap()` on an `Err` value: "Problem"
+
+* :rust:`.expect("Msg")` - like :rust:`unwrap`, with custom panic message
+
+  .. code:: rust
+
+    println!("Good: {}", good.expect("Expected"));
+    println!("Bad: {}", bad.expect("Expected"));
+
+  .. code:: output
+
+    Good: 42
+    thread 'main' panicked at src\main.rs:5:27:
+    Expected: "Problem"
+
+* :rust:`.unwrap_or(default)` - fallback value on error
+
+  .. code:: rust
+
+    println!("Good: {}", good.unwrap_or(-1));
+    println!("Bad: {}", bad.unwrap_or(-1));
+
+  .. code:: output
+
+    Good: 42
+    Bad: -1
 
 ------------------------
 Results vs. Exceptions

courses/rust_essentials/200_error_handling/05-try_conversions.rst

@@ -19,7 +19,6 @@ Automatic Error Type Conversion
       :font-size: tiny
 
       enum Reason { TooYoung, TooOld, }
-
       impl From<Reason> for String {
           fn from(reason: Reason) -> Self {
               match reason {
@@ -30,7 +29,6 @@ Automatic Error Type Conversion
               }
           }
       }
-
       // Error type is 'Reason'
       fn check_age(age: i32) -> Result<i32, Reason> {
           if age < 18 {
@@ -40,7 +38,6 @@ Automatic Error Type Conversion
           } else {
               Ok(age)
           }
-
       }
 
   .. container:: column
@@ -55,7 +52,6 @@ Automatic Error Type Conversion
           check_age(age)?;
           Ok(age)
       }
-
       match register(10) {
           Ok(age) => println!("Good enough {age}"),
           Err(e) => eprintln!("Problem: {e}"),
@@ -65,11 +61,10 @@ Automatic Error Type Conversion
           Err(e) => eprintln!("Problem: {e}"),
       }
 
-.. container:: latex_environment scriptsize
-
-  :error:`Problem: The user is too young.`
+.. code:: error
 
-  :error:`Problem: The user is too old.`
+  Problem: The user is too young.
+  Problem: The user is too old.
 
 .. note::