feat: mutate in closure with refcell

.github/workflows/pipeline.yaml

@@ -34,7 +34,7 @@ jobs:
           token: ${{ secrets.GITHUB_TOKEN }}
 
       - name: Test
-        run: cargo test --verbose
+        run: cargo test --release --verbose
 
   build:
     if: "!contains(github.event.head_commit.message, 'NO_CI')"

src/lib.rs

@@ -1,3 +1,2 @@
+pub mod mutate_in_closure;
 pub mod vec_any;
-
-pub use vec_any::Animal;

src/mutate_in_closure.rs

@@ -0,0 +1,22 @@
+use std::cell::RefCell;
+
+// Use RefCell to mutate a variable in a closure
+pub fn mutate_in_closure() {
+  let my_string = RefCell::new("hello".to_string());
+  let mutate = |new_val| {
+    *my_string.borrow_mut() = new_val;
+  };
+  // mutate in closure
+  mutate("hej".to_string());
+  assert_eq!(*my_string.borrow(), "hej");
+
+  *my_string.borrow_mut() = "bonjour".to_string();
+  assert_eq!(*my_string.borrow(), "bonjour");
+}
+
+mod tests {
+  #[test]
+  fn test_mutate_in_closure() {
+    super::mutate_in_closure();
+  }
+}