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.
Ruby metaprogramming examples.
1st review the built in read only variable self.
Let s begin with a basic example.
But it can be a bit confusing if you don t have a few specific examples.
For example when a user model is defined in rails with email as an attribute a method called find by email will be generated.
Ruby metaprogramming one of the most interesting aspects of ruby enables the programming language to achieve an extreme level of expressiveness.
Imagine that you have a database table for users that have columns such as name and email.
We re going to look at some popular open source projects using ruby metaprogramming.
Read the following articles.
In this article toptal engineer nikola todorovic demystifies.
In the example below here are some of the meta changes we re making to the program.
I m going to start with an example from the ruby on rails framework.
Metaprogramming is often presented as a very nebulous and dangerous concept one that is difficult to explain and hard.
That s why in this article.
Quote from the ruby object model.
Metaprogramming is the act of writing code that operates on code rather than on data.
Self quote from programming ruby 1 9.
Please refer our accompanying study notes and examples.
This involves inspecting and modifying a program as it runs using constructs exposed by the language.
When does self change.
Add a method named foldl to ruby s native array class.
2nd review singleton.
Metaprogramming is writing programs that write programs.
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 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.
Examples of metaprogramming a basic example.
All of them use some form of metaprogramming.
It is because of this very feature that many gems such as rspec and activerecord can work the way they do.
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.
Nov 20 th 2015 10 34 am.
Obviously the ruby on rails framework doesn t know what columns that you re going to have for the.
Ruby metaprogramming by example.
Self the current default object.
