Ruby is an interpreted, highlevel, generalpurpose programming language. Whats the deal with monkeypatching and why is everyone using it. Its suitable for small scripts as well as large applications. Monkeypatching is the dangerousyetfrequentlyuseful technique of. So you have to have a way to quickly learn those changes when you jump into a new codebase. So you search for how to moneykeypatch a class in ruby. Dr why do people think monkeypatching is ok instead of subclassing or using. Dynamic languages can be incredibly expressive and productive, but they allow downright evil practices like monkey patching. Check out 3 ways to monkey patch without making a mess for more info. Ruby is like a sharp knife, it can be extremely effective, but its usually your own fault if you cut yourself. Contribute to vbattsmonkeyfuck development by creating an account on github.
Monkey patching is the new black in the ruby community. Pass a block with the methods you want to add to the object, or any other modifications you want to make. Yes, its a weird name, but its a powerful and dangerous tool. These are two different concepts programming approaches. The purpose of ruby refinements is to scope changed behavior to a very specific area of code. Its easy to learn but also has some brainmelting complexities when you start getting into blocks, mixins, monkeypatching, and metaprogramming. Make monkey patching in ruby less risky with refinements. I dont actually think that monkey patching is destroying ruby, but i do. This is offered in some dynamic typing languages like javascript, perl, python etc. This is a bigger problem than clashing with another monkeypatching library. 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. Lets learn ruby classes, objects, and objectoriented programming. However, just because a tool is powerful, does not make it the right tool for the job. One of the best, and worst, features of ruby is monkeypatching, extending the languages builtin classes and modules to suit.
I havent, but it comes really useful when testing, to simulate sideeffecting functions or. 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. I dont use a whole lot of ruby in my day to day work, but it is a language that is. Monkey patching, for anyone who doesnt know, refers to the practice of extending or modifying existing code by. Until you hit weird bugs because a patch changed hash. In python, we can actually change the behavior of code at runtime. The first argument is the object you are patching, and the second argument is the name to use for the refinement if run under ruby 2. I have used the following technique described by justin weiss in 3 ways to monkeypatch without making a mess. However, a powerful tool in the wrong hands will cause endless amounts of pain and suffering. 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. Also id advise to use a module to wrap the monkey patch. Monkey patching, for anyone who doesnt know, refers to the practice of extending or modifying existing code by changing classes at runtime.
Its simple everything is an object and complex everything is an. Many people think that monkey patching is something that is restricted to dynamic languages like ruby and python. Rubys open classes are powerful but can easily be misused. Jul 11, 2008 ruby s open classes are powerful but can easily be misused. How to monkey patch a class in ruby posted by weston ganger sometimes you may need to override a method or add a new one to an existing class from a library or gem using a monkey patch.
Ruby on rails windows installation tutorial ruby 2. Monkey patching a way of programming in which we can modify or extend the executing code at runtime. The name monkey patching 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. Were in the future, and with github and bundler there is now rarely a need to monkey patch ruby code in your applications monkey patching is the dangerousyetfrequentlyuseful technique of reopening existing classes to change or add to their behavior. Rubyinstaller is the easiest and most used ruby environment on windows. Rubyinstaller combines the possibilities of native windows programs with the rich unix toolset of msys2 and the large repository of mingw. Monkey patching in python dynamic behavior in python, the term monkey patch refers to dynamic or runtime modifications of a class or module. Michael hartls ruby on rails 3 tutorial series is the way to go.
Its a very simple helper that adds html comments to the rendered source, so that you can inspect it easily in your browsers developer toolbar. It takes maturity to resist doing stupid shit like that, but its rampant in the rails community, i think because rails shameless abuses these things itself. Why rubys monkey patching is better than land mines. If youre looking to level up your js skills, its important you learn the beauty of monkey patching. As you see, ruby is like a sharp knife, it can be extremely effective, but its usually your own fault if you cut yourself. Pragmatic uses of monkey patching in javascript sitepoint. Monkey patching in python dynamic behavior geeksforgeeks. Every app with core patches feels a little bit different. Today one of my coworkers came and got me so that i could explain some weird python code theyd found. Ruby language monkey patching in ruby ruby tutorial. It ensures that the monkey patching happens before the first request. Monkey patching allows you to come up with a quick and dirty solution to a problem, but you should. Some do regard it as a useful necessity you cant avoid in order to patch bugs in third party code.
Why ruby s monkey patching is better than land mines. Windows subsystem for linux 2 moving into general availability with improved update process. Replace methods classes attributes functions at runtime, e. 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. Jul 12, 2008 monkey patching is the new black in the ruby community. Also, the windows executable was created with the ocra gem. Lets look at how go functions work and how we can modify them at runtime.
Monkey patching, while convenient, has some pitfalls that arent immediately obvious. This article looks at how to minimize the risk of opening classes, alternatives, and how other languages provide similar capabilities. Instance monkey patching in python oct 7 th, 20 monkey patching is the technique of swapping functions or methods with others in order to change a module, library or class behavior. 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. The above statement asserts that the ruby usage is incorrect but terms evolve, and thats not always a bad thing. This practice, known as monkey patching, is common in the ruby world, and since ruby 2, its been possible.
But use of some of its monkey patches are so prevalent in ruby. It supports multiple programming paradigms, including procedural, objectoriented, and functional programming. How to monkey patch a class in ruby solid foundation web. Jun 08, 2015 monkey patching is an essential skill for any advanced javascript developer. Dec 29, 2017 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. It was designed and developed in the mid1990s by yukihiro matz matsumoto in japan ruby is dynamically typed and uses garbage collection. Modifyextend behaviour of a thirdparty product without maintaining a private copy of the source code. Jun 17, 2015 ruby is like a sharp knife, it can be extremely effective, but its usually your own fault if you cut yourself. This can be used to great effect, for example rails fixnum date extensions, which. Monkey patching is an essential skill for any advanced javascript developer. Im most way through the ruby on rails tutorial michael hartl book and it gives. Monkey patching in particular is an extremely powerful tool. 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. You can see how i monkey patched dojos menu widget as a real example.
Monkey patching refers to the ability to modify existing code at runtime. Some im not so crazy about and its usually areas where they tried to copy perl. Starting off the list for examples of metaprogramming is monkey patching. One of the best, and worst, features of ruby is monkeypatching, extending the languages builtin classes and modules to suit your desires. Please note, that some gems are not yet compatible with ruby2.
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. May 09, 2017 whoa, hadnt heard that term for some years. Forget about that strange name and lets call it changing the behavior of the original code. Is it doing something like the following, or is it something else. This can be scary in a production environment because it is very difficult to debug this kind of code, but this can be very. Monkey patching devise or any rails gem ask question asked 6 years, 5 months ago. It dealt with cmake, but since it was internal code, i wont be able to show it here. I would like to know the exact meaning of monkey patching in ruby. Sometimes youre doing it the right way for the wrong reasons, other times you are doing it just flat out wrong. That is not true however, as computers are just dumb machines and we can always make them do what we want. Ruby provides us with a wealth of powerful tools to work with. 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. Ill try to carve out some time to dig into some of this stuff soon. Hopefully, after reading this post youll have a better idea what youre doing, and youll be monkey patching the right way for.
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. A subreddit for all questions related to programming in any language. Monkey patching in python is often see as being one of those things you should never do. 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. Heres an example of how it wont work with refinements. And ruby is a great language for beginners as well as professionals. Others will argue though that with so much software being open source these days that you should simply submit a.
Monkey patching is an object oriented programming technique that allows developers to. Apply the result of a patch at runtime to the state in memory, instead of the source code on disk. I spent a day and a half troubleshooting an issue caused by rails deleting constants and one of its libraries monkeypatching a mime library. Instead, i wrote up something that has the same issues so you can see what i consider continue reading python. Sometimes you may need to override a method or add a new one to an existing class from a library or gem using a monkey patch. According to the creator, ruby was influenced by perl, smalltalk, eiffel. Contribute to vbatts monkey fuck development by creating an account on github. Hopefully, after reading this post youll have a better idea what youre doing, and youll be monkey patching the right way for the right reasons. Monkey patching has been used for a long time for modifying code behavior.
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