Ruby monkey patching culture

Monkey patching is less and less frequent im maintaining pure ruby, but also rails app since 2005, is generally considered a bad practice railscentrism is gradually becoming a thing of the past see gems like hanami, roda, sequel, kiba, dryrb etc. When we see an opportunity to move a util method to one of the existing rubys standard classes, thats when we open the existing ruby class and add that method there. About more non rails stuff, i started writing small text processing scripts in ruby a few years ago. Hopefully, after reading this post youll have a better idea what youre doing, and. One of the best, and worst, features of ruby is monkeypatching, extending the languages builtin classes and modules to suit your desires. This practice, known as monkey patching, is common in the ruby world, and since ruby 2, its been possible to mitigate some of the risks using refinements. I havent, but it comes really useful when testing, to simulate sideeffecting functions or to silence expected errors and warnings. However, just because a tool is powerful, does not make it the right tool for the job. This process of changing classes runtime is known as monkeypatching in the ruby community. Why rubys monkey patching is better than land mines. I hope you will find this video useful as previous ones. A common approach in ruby is to consider overriding existing methods to be monkey patching, but adding methods not to be, even though most nonruby definitions would include both. Whats the deal with monkeypatching and why is everyone.

Refinements ruby monkeypatching redifined red panthers. You can read the definition in the wikipedia link i provided, but in short, it is a way to modify the behavior of a class or instance of a class at runtime without changing the source of that class or instance. Overall ive been pretty happy with its features, ecosystem and libraries for web development, however my previous dabbles into python have left me longing for a yet unimplemented feature. Forget about that strange name and lets call it changing the behavior of the original code. These are two different concepts programming approaches. You can see how i monkey patched dojos menu widget as a real example. Its a very simple helper that adds html comments to the rendered source, so that you can inspect it. Compared to utility classes, its a hell of a lot more convenient, and it reads better. Monkey patching is rarely used in daytoday code in the sense of overwriting core libraries. Ive been using ruby for quite some time, but it was only recently that i found a hidden gem in the standard library, the set class. Monkey patching allows you to come up with a quick and dirty solution to a problem, but you should use it very sparingly. The above statement asserts that the ruby usage is incorrect but terms evolve, and thats not always a bad thing.

Pragmatic uses of monkey patching in javascript sitepoint. Monkeypatching is the technique of swapping functions or methods with others in order to change a module, library or class behavior there are some people with strong opinions about it. To illustrate monkey patching well make some changes to the good old string core class. Were in the future, and with github and bundler there is now rarely a need to monkeypatch ruby code in your applications monkeypatching is the dangerousyetfrequentlyuseful technique of reopening existing classes to change or add to their behavior. Starting off the list for examples of metaprogramming is monkey patching. Rubys open classes are powerful but can easily be misused. However, in the larger python and ruby communities this distinction isnt usually made and monkey patching usually refers to any reopening of class, regardless of intent. This videos shows you what monkey patching is in ruby. Ruby makes it easy to extend its builtin classes, which can be very convenient and lead to more readable codebut it can also be dangerous. Monkey patching in javascript when working on a project, we often use libraries that implement methods that arent builtin in the programming language in use. This is a community driven project, so you are encouraged to. Currently im playing a little creating an immutable version of dict. In ruby, its possible to add methods to absolutely any class including string, integer and other core classes. Monkey patching is reopening the existing classes or methods in class at runtime and changing the behavior, which should be used cautiously, or you should use it only when you really need to.

The ability to change the way classes behave at runtimeaka monkeypatching has been used by many libraries and frameworks to decorate rubys core classes with additions andor replacements. Im taking the ruby standard library class numeric parent of all number based classes in ruby such as integer and float, opening it back up and. Ruby is like a sharp knife, it can be extremely effective, but its usually your own fault if you cut yourself. This article looks at how to minimize the risk of opening classes, alternatives, and how other languages provide similar capabilities. I wrote the following code which will allow me to multiply a vektor with a number and two vectors with each other. Many of rails way elements are associated with how they do it in ruby and too much magic, including infamous convention over configuration principleand extensive monkeypatching if whatever rails team wants to fix. Take the example below where i am implementing a simplified version of a monkeypatch that rails does. If you are familiar with the mathematical concept of a set, then rubys implementation will hold no surprises for you. It is also possible to specially name a patched ruby see named rubies for more details. Sometimes youre doing it the right way for the wrong reasons, other times you are doing it just flat out wrong.

If that is the source of the idea that monkey patching is derogatory, then he really misunderstood something. As python is a dynamic programming language, classes are mutable so you can reopen them and modify or even replace them. Monkey patching is an object oriented programming technique that allows developers to. Monkey patching is the new black in the ruby community. This practice, known as monkey patching, is common in the ruby world, and since ruby. Ruby is oblidged to rails with its current popularity, but also with questionable reputation. Monkeypatching, single responsibility principle, and. Monkey patching hereafter referred to as mp is a technique to override, extend or even suppress the default behavior of a code segment without changing its original. In ruby, python, and many other dynamic programming languages, the term monkey patch only refers to dynamic modifications of a class or module at runtime, motivated by the intent to patch existing thirdparty code as a workaround to a bug or feature which does not act as desired. Make monkey patching in ruby less risky with refinements. In this talk you will learn what monkey patching is all about and whether its. Even activesupport mostly does adding to the stdlib, not changing existing behaviors.

Its a problem in the language, but not as big as youd think due to culture. A monkey patch being a subtle change to an existing algorithm only observable if you have seen both the new and the base specification. However the last thing i wrote in ruby is a scraper for a web site, a few hours after patching a rails app ive been maintaining for a customer for at least five years. As such, this page will be updated on a regular basis to include additional information and cover emerging ruby techniques. But just like any of ruby s sharp edges, you have to take extra care when you use them. This resource contains a collection of ruby best practices and ruby tips provided by our toptal network members. I would like to know the exact meaning of monkey patching in ruby. Unfortunately, the majority of popular articles are very controversial, and i feel obliged to write a response on one of the so called pros of ruby. Infoq talked to yusuke to learn more about the big new features of ruby. Is there a purely technical term for monkey patching. These libraries dont cover all the possibilities, so they might lack one or more crucial features we need. Now the question is ruby monkey patching is it good or bad before answering the question lets understand what monkey patching is. If youre looking to level up your js skills, its important you learn the beauty of monkey patching.

It is a powerful technique that has become popular in the ruby community at least in part because the ruby language makes it so easy. Going with the most general of definitions, such as a way to extend or modify the runtime code of dynamic languages is problematic in ruby, because it would cover. If you have not subscribed the channel please hit the subscribe button. Monkey patching, for anyone who doesnt know, refers to the practice of extending or modifying existing code by changing classes at runtime. In todays tutorial well be looking at monkey patching in ruby. Hello friends, in this video you will learn about monkey patching. In ruby, the term monkey patch was misunderstood to mean any dynamic modification to a class and is often used as a synonym for dynamically modifying any class at runtime. And that could lead to side effect if we are not careful. Duck typing a programming concept that is primarily concerned with the methods that can be run on an object rather than the class of the object. Lets start with writing the spec of where i want the model to be i am using validattribute if the specs dont look familiar, i suggest you try it test spec your validations. To the point that smart, experienced hackers reach for a monkey patch as their tool of first resort, even when a simpler, more traditional solution is possible. There appears to be trend where specifications monkey patch a base specification. When you do it well, it makes your code feel more like ruby. The name monkeypatching basically comes from older times where you needed to do hot patches fixes or changeinject new functionality, especially into 3rd party code which you depended on, but couldnt change the original.

Writing a class that is really immutable in python is really hard, if not impossible. One of the most useful among these specialities is that, in ruby, all classes are mutable. Ruby provides us with a wealth of powerful tools to work with. Monkey patching in particular is an extremely powerful tool.