iterators1 solution

exercises/18_iterators/iterators1.rs

@@ -1,8 +1,6 @@
 // When performing operations on elements within a collection, iterators are
 // essential. This module helps you get familiar with the structure of using an
 // iterator and how to go through elements within an iterable collection.
-//
-// Make me compile by filling in the `???`s
 
 fn main() {
     // You can optionally experiment here.
@@ -10,19 +8,18 @@ fn main() {
 
 #[cfg(test)]
 mod tests {
-    use super::*;
-
     #[test]
     fn iterators() {
-        let my_fav_fruits = vec!["banana", "custard apple", "avocado", "peach", "raspberry"];
+        let my_fav_fruits = ["banana", "custard apple", "avocado", "peach", "raspberry"];
 
-        let mut my_iterable_fav_fruits = ???;   // TODO: Step 1
+        // TODO: Create an iterator over the array.
+        let mut fav_fruits_iterator = ???;
 
-        assert_eq!(my_iterable_fav_fruits.next(), Some(&"banana"));
-        assert_eq!(my_iterable_fav_fruits.next(), ???);     // TODO: Step 2
-        assert_eq!(my_iterable_fav_fruits.next(), Some(&"avocado"));
-        assert_eq!(my_iterable_fav_fruits.next(), ???);     // TODO: Step 3
-        assert_eq!(my_iterable_fav_fruits.next(), Some(&"raspberry"));
-        assert_eq!(my_iterable_fav_fruits.next(), ???);     // TODO: Step 4
+        assert_eq!(fav_fruits_iterator.next(), Some(&"banana"));
+        assert_eq!(fav_fruits_iterator.next(), ???); // TODO: Replace `???`
+        assert_eq!(fav_fruits_iterator.next(), Some(&"avocado"));
+        assert_eq!(fav_fruits_iterator.next(), ???); // TODO: Replace `???`
+        assert_eq!(fav_fruits_iterator.next(), Some(&"raspberry"));
+        assert_eq!(fav_fruits_iterator.next(), ???); // TODO: Replace `???`
     }
 }

rustlings-macros/info.toml

@@ -886,22 +886,9 @@ https://doc.rust-lang.org/stable/book/ch11-01-writing-tests.html#checking-for-pa
 name = "iterators1"
 dir = "18_iterators"
 hint = """
-Step 1:
-
-We need to apply something to the collection `my_fav_fruits` before we start to
-go through it. What could that be? Take a look at the struct definition for a
-vector for inspiration:
-https://doc.rust-lang.org/std/vec/struct.Vec.html
-
-Step 2 & step 3:
-
-Very similar to the lines above and below. You've got this!
-
-Step 4:
-
 An iterator goes through all elements in a collection, but what if we've run
 out of elements? What should we expect here? If you're stuck, take a look at
-https://doc.rust-lang.org/std/iter/trait.Iterator.html for some ideas."""
+https://doc.rust-lang.org/std/iter/trait.Iterator.html"""
 
 [[exercises]]
 name = "iterators2"

solutions/18_iterators/iterators1.rs

@@ -1 +1,26 @@
-// Solutions will be available before the stable release. Thank you for testing the beta version 🥰
+// When performing operations on elements within a collection, iterators are
+// essential. This module helps you get familiar with the structure of using an
+// iterator and how to go through elements within an iterable collection.
+
+fn main() {
+    // You can optionally experiment here.
+}
+
+#[cfg(test)]
+mod tests {
+    #[test]
+    fn iterators() {
+        let my_fav_fruits = ["banana", "custard apple", "avocado", "peach", "raspberry"];
+
+        // Create an iterator over the array.
+        let mut fav_fruits_iterator = my_fav_fruits.iter();
+
+        assert_eq!(fav_fruits_iterator.next(), Some(&"banana"));
+        assert_eq!(fav_fruits_iterator.next(), Some(&"custard apple"));
+        assert_eq!(fav_fruits_iterator.next(), Some(&"avocado"));
+        assert_eq!(fav_fruits_iterator.next(), Some(&"peach"));
+        assert_eq!(fav_fruits_iterator.next(), Some(&"raspberry"));
+        assert_eq!(fav_fruits_iterator.next(), None);
+        //                                     ^^^^ reached the end
+    }
+}