iterators3 solution

exercises/18_iterators/iterators3.rs

@@ -1,40 +1,26 @@
-// This is a bigger exercise than most of the others! You can do it! Here is
-// your mission, should you choose to accept it:
-// 1. Complete the divide function to get the first four tests to pass.
-// 2. Get the remaining tests to pass by completing the result_with_list and
-//    list_of_results functions.
-
 #[derive(Debug, PartialEq, Eq)]
 enum DivisionError {
-    NotDivisible(NotDivisibleError),
     DivideByZero,
+    NotDivisible,
 }
 
-#[derive(Debug, PartialEq, Eq)]
-struct NotDivisibleError {
-    dividend: i32,
-    divisor: i32,
-}
-
-// Calculate `a` divided by `b` if `a` is evenly divisible by `b`.
+// TODO: Calculate `a` divided by `b` if `a` is evenly divisible by `b`.
 // Otherwise, return a suitable error.
 fn divide(a: i32, b: i32) -> Result<i32, DivisionError> {
     todo!();
 }
 
-// Complete the function and return a value of the correct type so the test
-// passes.
-// Desired output: Ok([1, 11, 1426, 3])
-fn result_with_list() -> () {
-    let numbers = vec![27, 297, 38502, 81];
+// TODO: Add the correct return type and complete the function body.
+// Desired output: `Ok([1, 11, 1426, 3])`
+fn result_with_list() {
+    let numbers = [27, 297, 38502, 81];
     let division_results = numbers.into_iter().map(|n| divide(n, 27));
 }
 
-// Complete the function and return a value of the correct type so the test
-// passes.
-// Desired output: [Ok(1), Ok(11), Ok(1426), Ok(3)]
-fn list_of_results() -> () {
-    let numbers = vec![27, 297, 38502, 81];
+// TODO: Add the correct return type and complete the function body.
+// Desired output: `[Ok(1), Ok(11), Ok(1426), Ok(3)]`
+fn list_of_results() {
+    let numbers = [27, 297, 38502, 81];
     let division_results = numbers.into_iter().map(|n| divide(n, 27));
 }
 
@@ -52,19 +38,13 @@ mod tests {
     }
 
     #[test]
-    fn test_not_divisible() {
-        assert_eq!(
-            divide(81, 6),
-            Err(DivisionError::NotDivisible(NotDivisibleError {
-                dividend: 81,
-                divisor: 6
-            }))
-        );
+    fn test_divide_by_0() {
+        assert_eq!(divide(81, 0), Err(DivisionError::DivideByZero));
     }
 
     #[test]
-    fn test_divide_by_0() {
-        assert_eq!(divide(81, 0), Err(DivisionError::DivideByZero));
+    fn test_not_divisible() {
+        assert_eq!(divide(81, 6), Err(DivisionError::NotDivisible));
     }
 
     #[test]
@@ -74,14 +54,11 @@ mod tests {
 
     #[test]
     fn test_result_with_list() {
-        assert_eq!(format!("{:?}", result_with_list()), "Ok([1, 11, 1426, 3])");
+        assert_eq!(result_with_list().unwarp(), [1, 11, 1426, 3]);
     }
 
     #[test]
     fn test_list_of_results() {
-        assert_eq!(
-            format!("{:?}", list_of_results()),
-            "[Ok(1), Ok(11), Ok(1426), Ok(3)]"
-        );
+        assert_eq!(list_of_results(), [Ok(1), Ok(11), Ok(1426), Ok(3)]);
     }
 }