Examples of metaprogramming a basic example.
Ruby metaprogramming examples.
Ruby is an interpreted high level general purpose programming language it was designed and developed in the mid 1990s by yukihiro matz matsumoto in japan.
That s why in this article.
In this article toptal engineer nikola todorovic demystifies.
Please refer our accompanying study notes and examples.
Nov 20 th 2015 10 34 am.
This involves inspecting and modifying a program as it runs using constructs exposed by the language.
Metaprogramming is often presented as a very nebulous and dangerous concept one that is difficult to explain and hard to wrap your head around and thus should be avoided.
In ruby the term metaprogramming refers to the dynamic nature of the language which allows you to define and redefine methods and classes at runtime.
Self quote from programming ruby 1 9.
Obviously the ruby on rails framework doesn t know what columns that you re going to have for the.
Ruby is dynamically typed and uses garbage collection it supports multiple programming paradigms including procedural object oriented and functional programming according to the creator ruby was influenced by perl smalltalk eiffel.
Self the current default object.
I m going to start with an example from the ruby on rails framework.
Add a method named foldl to ruby s native array class.
In the example below here are some of the meta changes we re making to the program.
Ruby metaprogramming by example.
1st review the built in read only variable self.
Let s begin with a basic example.
Let s start learning ruby metaprogramming.
Imagine that you have a database table for users that have columns such as name and email.
In ruby the term metaprogramming refers to the dynamic nature of the language which allows you to define and redefine methods and classes at runtime.
Ruby metaprogramming one of the most interesting aspects of ruby enables the programming language to achieve an extreme level of expressiveness.
Metaprogramming is often presented as a very nebulous and dangerous concept one that is difficult to explain and hard.
Quote from the ruby object model.
It is because of this very feature that many gems such as rspec and activerecord can work the way they do.
2nd review singleton.
Metaprogramming is the act of writing code that operates on code rather than on data.
When does self change.
All of them use some form of metaprogramming.
But it can be a bit confusing if you don t have a few specific examples.
You may have read about ruby metaprogramming before.
We re going to look at some popular open source projects using ruby metaprogramming.
