Js monkey patching ruby

A guide walking readers through a real world use case of monkey patching in ruby, dealing with other gems and orms. Make monkey patching in ruby less risky with refinements. 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. This article looks at how to minimize the risk of opening classes, alternatives, and how other languages provide similar capabilities. This means applying a monkey patch to a 3rd party library will not change the library itself but only the local copy of the library you have on your machine. Monkey patching in particular is an extremely powerful tool. That time monkey patching took 2 days off my life a geek with a hat. A monkey patch is a way to change, extend or modify a library, plugin, or supporting system software locally. We can do the same kind of thing in javascript, of course. Knowing the difference can make a difference in your programming. In this article i will show you how to modify jquery using a technique called monkey patching or duck punching. This includes the standard ruby classes like string, array. Add method to existing class you dont own in javascript. It turned out that one of our more excruciating pain points was differences in monkeypatching of standard ruby classes from one version to the next.

Because ruby is an interpreted language objects are open and can be modified at runtime. One thing ive never been crazy about is monkey patching. Ruby allows for monkey patching a goofy name for an incredibly powerful technique. Monkey patching is something thats made possible thanks to the concept of open classes. Monkey patching, for anyone who doesnt know, refers to the practice of extending or modifying existing code by. Conventional wisdom says to steer clear of this activity, but i think sometimes it is inevitable.

A monkey patch is a way for a program to extend or modify supporting system software locally affecting only the running instance of the program. An alternative etymology is that it refers to monkeying about. This videos shows you what monkey patching is in ruby. Monkey patching is an essential skill for any advanced javascript developer.

Ruby is like a sharp knife, it can be extremely effective, but its usually your own fault if you cut yourself. Monkey patching can only be done in dynamic languages, of which python is a good example. 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. This is a common technique in dynamic languages like javascript, python, ruby for replacing the behavior of a program during runtime.

Thats where you try to establish an objects suitability for some purpose, using the principle, if it walks like a duck and it quacks like a duck, then it must be a duck. Monkey patching hereafter referred to as mp is a technique to override, extend or even suppress the default behavior of. Changing a method at runtime instead of updating the object definition is one example. I dont actually think that monkey patching is destroying ruby, but i do think the proliferation of the technique has real and troubling implications for rubys future. A guide to responsible monkey patching in javascript. Autoplay when autoplay is enabled, a suggested video will automatically play next. Im actually really surprised go doesnt just let you. Yes thats right, you can actually reopen any class and change how it works. While both have their strengths, a careful analysis can help you select the one most appropriate for your development needs. Monkeypatching, overriding, and decorating methods in. Using this function allows you to add functionality to existing classes, as well as override properties of the class. I worked with rails teams for about seven years before the team that started my current shop got bit hard by a version migration that went south. The word guerrilla, homophonous with gorilla or nearly so, became monkey, possibly to make the patch sound less intimidating.

If youre looking to level up your js skills, its important you learn the beauty of monkey patching. 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. Monkey patching is a programming technique popular in the ruby world and nippedinthebud by the javascript community. Monkeypatching is extremely useful when you want to modify the behavior of some methods, but you dont want to alter its source code. 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. One of the most powerful aspects of ruby is the ability to reopen any class and change its methods. This practice, known as monkey patching, is common in the ruby world, and since ruby 2, its been possible.

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. Why rubys monkey patching is better than land mines. Please enable javascript to view the comments powered by disqus. Although rubys array class does not define a special method for obtaining the second. The term monkey patch seems to have come from an earlier term, guerrilla patch, which referred to changing code sneakily and possibly incompatibly with other such patches at runtime. To associate your repository with the monkeypatching topic, visit. Whenever you monkey patch a class you are potentially creating a headache at some point in the future when things go wrong. The decorator pattern and monkey patching have yet another name, coined by ruby hackers who decided that they needed a name that. My personal opinion is monkey patching should only be done to. You can see how i monkey patched dojos menu widget as a real example. When working on a project, we often use libraries that implement methods that arent builtin in the. Rubys open classes are powerful but can easily be misused. However, a powerful tool in the wrong hands will cause endless amounts of pain and suffering.

In python, we can actually change the behavior of code at runtime. 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. One of the most useful among these specialities is that, in ruby, all classes are mutable. In todays tutorial well be looking at monkey patching in ruby. The two methods above require changing the system to avoid monkey patching. I opened up the irb and fired in simple arithmetic operations. Refinements ruby monkeypatching redifined red panthers. The ability to change the way classes behave at runtimeaka monkeypatching has been used by many libraries and frameworks to decorate rubys. 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. Now the question is ruby monkey patching is it good or bad before answering the question lets understand what monkey patching is. Is it doing something like the following, or is it something else.

Monkey patching is not a panacea for putting your own spin on js methods and functions. Monkey patching is the term used to describing extending a classs functionality as shown above, or overwrite existing methods. Just because monkey patching offers you an easy solution, does not mean that you should always take that path. Erb is a ruby class that accepts text, and evaluates and replaces ruby code surrounded by. Erb stands for embedded ruby, and is used to insert ruby variables inside templates, e. Yes, i understand that you can use ruby without monkey patching but what i am wondering if the chief reason developers reach for ruby is there love for monkey patching. To be fair monkey patching in ruby and js land is also unsafe and can be nutty but they dont have compilers.

These are two different concepts programming approaches. The best way to avoid monkey patching is to actually just send a pull request. At any time during program execution, you can augment existing code by simply redefining it. Some languages like ruby and javascript have open classes which allow you to modify interfaces of even core classes like numbers, strings. A collection of helpful methods and monkey patches for arrays, objects, numbers, and strings in javascript westongangerrearmed js. Monkey patching in python dynamic behavior in python, the term monkey patch refers to dynamic or runtime modifications of a class or module. Ruby on rails development or python, what sets them apart from each other. Especially when used on builtin objects, monkey patching can interfere with the evolution of the language.

I would like to know the exact meaning of monkey patching in ruby. 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. Monkey patching is not rubyexplicit, its done all over javascript too, with negative imo effects. In ruby, a monkey patch mp is any dynamic modification to a class and is often used as a synonym for dynamically modifying any class add new or overwrite existing methods at runtime. This assignment had 8 specs to be met and im stuck now with one left and im not sure what to do im only going to give you the rspecs and written requirements for the part that im having trouble w since everything else seems to be passing. Forget about that strange name and lets call it changing the behavior of the original code. 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. Until you hit weird bugs because a patch changed hash. For example, when attaching some extra behavior or when working around an issue in a thirdparty library. This section shows the preferred and least invasive method of monkey patching, should changing the system not be an option. There are inherent dangers associated with the practice. Monkey patching is the new black in the ruby community. Monkey patching, like singletons, is a subtle form of global state, where its not a bunch of objects hidden somewhere that is modified and alters the results of your test singletons, but its.

How to use monkey patch in ruby in this article, we introduce the concept of monkey patches in ruby, when to use them, and how to use them effectively in. Monkey patching is especially useful for modifying code from third party vendors. Whats the deal with monkeypatching and why is everyone. Some im not so crazy about and its usually areas where they tried to copy perl. People call this monkey patching, but to be precise, the phrase monkey.