Ruby Monkey Patch Super

Ruby s open classes are powerful but can easily be misused.

Ruby monkey patch super.

In the most recent ruby 2 7 upgrade at github we monkey patched warning warn to be able to turn warnings into exceptions. To check out the full results please visit my github profile. This module is based on the wonderful monkey patch by paul driver. Although i did not create a library i would expect people to use i learned a lot about how ruby works and had a great time solving the problem.

You can monkey patch module kernel to get methods available in main. Due to ruby s open classes you can redefine or add functionality to existing classes. Grandma s berry patch backshall ruby wants to pick lots of berries from grandma s berry patch so grandma can make her surprise berry recipe. Therefore a monkey patch might break code which doesn t expect the extended behavior and multiple monkey patches for the same class might cause conflicts to solve these problems refinements provide a way to extend classes locally.

All users of the monkey patched class see the same changes. Until ruby 2 0 there was no way to add code below a class only above it. Interface to patch package is slightly different see previous item for the cause. But with prepend you can override a method in a class with a method from a module and still access the class s implementation with super.

This is called a monkey patch. Unfortunately the scope of such changes is global. This can cause unintended side effects or breakage of programs. Deprecation warnings and other warnings in ruby have a category deprecated etc but those categories aren t exposed or accessible.

The knowledge gained from this adventure was totally worth it. Subscribe to treehouse direct for new clips episodes and more. Monkey patching is a powerful feature of ruby however it affects globally in a program. Max spends plenty of time in his super hero outfit.

This article looks at how to minimize the risk of opening classes alternatives and how other languages provide similar capabilities. Watch as he helps ruby and friends.