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[:hello, "world", :this, :crushes, "an entire", "hash"]
```
+## [`Override`](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/lib/gitlab/utils/override.rb)
+
+* This utility could help us check if a particular method would override
+ another method or not. It has the same idea of Java's `@Override` annotation
+ or Scala's `override` keyword. However we only do this check when
+ `ENV['STATIC_VERIFICATION']` is set to avoid production runtime overhead.
+ This is useful to check:
+
+ * If we have typos in overriding methods.
+ * If we renamed the overridden methods, making original overriding methods
+ overrides nothing.
+
+ Here's a simple example:
+
+ ``` ruby
+ class Base
+ def execute
+ end
+ end
+
+ class Derived < Base
+ extend ::Gitlab::Utils::Override
+
+ override :execute # Override check happens here
+ def execute
+ end
+ end
+ ```
+
+ This also works on modules:
+
+ ``` ruby
+ module Extension
+ extend ::Gitlab::Utils::Override
+
+ override :execute # Modules do not check this immediately
+ def execute
+ end
+ end
+
+ class Derived < Base
+ prepend Extension # Override check happens here, not in the module
+ end
+ ```
+
## [`StrongMemoize`](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/lib/gitlab/utils/strong_memoize.rb)
* Memoize the value even if it is `nil` or `false`.