option2 solution

exercises/12_options/options2.rs

@@ -9,7 +9,7 @@ mod tests {
         let target = "rustlings";
         let optional_target = Some(target);
 
-        // TODO: Make this an if let statement whose value is "Some" type
+        // TODO: Make this an if-let statement whose value is `Some`.
         word = optional_target {
             assert_eq!(word, target);
         }
@@ -20,15 +20,15 @@ mod tests {
         let range = 10;
         let mut optional_integers: Vec<Option<i8>> = vec![None];
 
-        for i in 1..(range + 1) {
+        for i in 1..=range {
             optional_integers.push(Some(i));
         }
 
         let mut cursor = range;
 
-        // TODO: make this a while let statement - remember that vector.pop also
-        // adds another layer of Option<T>. You can stack `Option<T>`s into
-        // while let and if let.
+        // TODO: Make this a while-let statement. Remember that `Vec::pop()`
+        // adds another layer of `Option`. You can do nested pattern matching
+        // in if-let and while-let statements.
         integer = optional_integers.pop() {
             assert_eq!(integer, cursor);
             cursor -= 1;

rustlings-macros/info.toml

@@ -616,9 +616,9 @@ Check out:
 - https://doc.rust-lang.org/rust-by-example/flow_control/if_let.html
 - https://doc.rust-lang.org/rust-by-example/flow_control/while_let.html
 
-Remember that `Option`s can be stacked in `if let` and `while let`.
+Remember that `Option`s can be nested in if-let and while-let statements.
 
-For example: `Some(Some(variable)) = variable2`
+For example: `if let Some(Some(x)) = y`
 
 Also see `Option::flatten`
 """

solutions/12_options/options2.rs

@@ -1 +1,37 @@
-// Solutions will be available before the stable release. Thank you for testing the beta version 🥰
+fn main() {
+    // You can optionally experiment here.
+}
+
+#[cfg(test)]
+mod tests {
+    #[test]
+    fn simple_option() {
+        let target = "rustlings";
+        let optional_target = Some(target);
+
+        // if-let
+        if let Some(word) = optional_target {
+            assert_eq!(word, target);
+        }
+    }
+
+    #[test]
+    fn layered_option() {
+        let range = 10;
+        let mut optional_integers: Vec<Option<i8>> = vec![None];
+
+        for i in 1..=range {
+            optional_integers.push(Some(i));
+        }
+
+        let mut cursor = range;
+
+        // while-let with nested pattern matching
+        while let Some(Some(integer)) = optional_integers.pop() {
+            assert_eq!(integer, cursor);
+            cursor -= 1;
+        }
+
+        assert_eq!(cursor, 0);
+    }
+}