1. Tech

Your suggestion is on its way!

An email with a link to:

http://ruby.about.com/popular.htm

was emailed to:

Thanks for sharing About.com with others!

Ruby: Most Popular Articles

These articles are the most popular over the last month.
How to Fix Missing Class or Module Errors
Problem: You encounter an error reading NameError: uninitialized constant Something or NameError: uninitialized constant Object::Something (with various class names in place of Something).
A Quick Guide to Forming Command Line Arguments...
Use command-line arguments to pass parameters to your Ruby scripts from the command line.
A Quick Guide to Creating and Using Hashes in...
This article explains and teaches how to use a associative arrays (hashes) as a way to store multiple variables in one data structure.
What Every Coder Should Know About Running Ruby...
Learn how to use the command line interface on Windows, Linux and OS X to run rb files and use the interactive Ruby program. Page 2.
A Quick Guide to Using Environmental Variables...
Using environment variables in Ruby.
How to Create Arrays in Ruby
This article explains and teaches how to use a arrays as a way to store multiple variables in one data structure.
A Quick Guide to Installing Ruby on Linux
How to install Ruby on the Linux operating system.
Checking Your Email with Ruby
How to check POP3 email accounts in Ruby.
NameError: undefined local variable or method...
Problem: You encounter an error reading NameError: undefined local variable or method `a' for # or NameError: undefined local variable or method `a' for main:Object (with various identifiers in place of 'a').
How to Use 'Loops' in Ruby (While, Until, Each,...
Loops, including while and include loops, are one of the most commonly used constructs in computer programs. Page 2.
Using Strings
Using and manipulating strings and substrings in Ruby. Page 4.
Using the 'split' Method in Ruby
String manipulation using the split method in Ruby. Split strings into a list of substrings.
How to Use Comments for Ruby Code
Use comments to annotate your Ruby code.
How to Use OptionParser: Ruby's Powerful...
Ruby comes equipped with a powerful and flexible tool to parse command-line options, OptionParser. The class is an alternative to GetoptLong for analyzing command line options.
Splitting Strings
Unless user input is a single word or number, that input will need to be split, or turned into a list of strings or numbers.
How to Use 'DIR.GLOB' with Directories in Ruby
In the previous article in this series, we discussed the basics of the Dir class. Particularly useful was the Dir.for each method for iterating over all files in a directory. However, this only goes so far. What if you want to iterate over only some files (for example, just XML files) in a directory?
Making Deep Copies in Ruby
It's often necessary to make a copy of a value in Ruby. While this may seem simple, and it is for simple objects, as soon as you have to make a copy of a data structure with multiple array or hashes on the same object, you will quickly find there are many pitfalls.
How to Create a URL Shortener in Ruby on Rails...
URL shortening is a useful feature for any Rails application. Making it easy for people to share links to your content is always a good thing.
Here's What Ruby Is
What type of language is the Ruby programming language?
How to Use 'Ternary' (Conditional) Operators in...
class="no-js" itemscope itemtype="http://schema.org/Article" > itemprop="description" >The ternary (or
How to Use Case (Switch) Statements in Ruby
The case statement is a control structure that is usually quite limited in other programming langauges. However, it's quite powerful and flexible in Ruby.
How to Use 'OptionParser' for Command Parsing...
Using OptionParser to parse command line options is a preferable alternative to GetoptLong or looking through ARGV manually. But how do you use it?
Instantiation and the Initialize Method
Ruby objects are instantiated using the Class.new method, and initialize using their own initialize methods.
Part 3: Implementing
In this part, we'll implement a complete working application.
Using Attributes
There are two basic things you can do with an object: call a method on it and access an attribute. Ruby doesn't make a distinction between these things, but it does give you some tools to make some methods act like attributes.
3 Ruby Scripts for Twitter Automation
Exploring and knowing the Twitter API is fine, but what do you do from there? Here are 3 practical scripts to help you follow followers on Twitter, update your Twitter account via an RSS feed and to be notified of your friend's new Tweets as they come in.
Keyword Arguments
Until Ruby 2.0, Ruby has not had true keyword arguments. You could simulate them using a hash, but as of Ruby 2.0 there's no longer any need to do that.
RubyMine 5.0
I've always been a Vim person. Just give me a good solid editor and I'll take it from there. But I decided to give RubyMine a good honest try, and here's what I think about it.
A Simple Guide to Using Aliases in Ruby
Aliasing is a powerful Ruby feature that allows more than one method to be referred to by multiple names. This can be used to give a programmer more expressive options or to create copies of a method, allowing you to change the behavior of a class.
Generating Random Numbers in Ruby
It's often useful in games, simulation and unit testing to generate random numbers, Ruby provides easy access to a pseudo-random number generator.
A Simple Guide to Using the Command Line in Ruby
How to use the command line interface on Windows, Linux and OS X to run Ruby scripts and use the interactive Ruby program.
Global Variables
Global variables are not often used in Ruby, however, you should at least understand their usage should you ever encounter them.
How to Use String Substitution in Ruby
class="no-js" itemscope itemtype="http://schema.org/Article" > itemprop="description" >Splitting a string
Using the Logger Library--How to Write Log...
How to use the logger library to create and write to log files in Ruby.
Wondering if You Should Overlook The "Require"...
The 'require' method is the reusable code mechanism in Ruby. It allows you to import other source files into your programs.
How to Install Gems from Git Repositories in Ruby
How to install gems from git repositories.
Instance Variables
Instance variables are some of the most common and important variables types in Ruby. They begin with the at sign (@) and allow objects to track their internal state.
How to Install JSON Gem in Ruby
It's easy to jump into parsing and generating JSON in Ruby with the json gem. It provides an API for parsing JSON from text as well as generating JSON text from arbitrary Ruby objects. It's easily the most used JSON library in Ruby.
Net::SSH--The SSH (Secure Shell) Protocol
Net::SSH is a way for Ruby to interact with SSH (Secure Shell) protocol. It relies on the OpenSSL library for encryption.
Two Dimensional Arrays in Ruby
We'll use a two dimensional array to represent the 2048 game board, but how do we create a 2D array in Ruby?
Making a Text Adventure Game in Ruby
Text adventure games were a very popular game genre on minicomputers and microcomputers from the 1970's through the 1990's. This article series will take you through each step of making a text adventure game in Ruby.
Quick Rails 4 Blog Tutorial
What do you do when a new version of Rails comes out? Build a blog, of course. The blog is kind of the hello, world application of the web application world.
Installing RVM on Linux
Installing the Ruby Version Manager (RVM) on Linux
Can I add empty directories to Git repositories?
Can I add empty directories to Git repositories?
How to Install Ruby
How to install the Ruby interpreter on Windows, Linux and OS X.
Iterating Over Strings
It's not a very common thing in Ruby. You have more sophisticated string tools (such as split or scan), but there are times when you'd want to iterate over the characters in a string. Unicode complicates this matter, but Ruby makes it simple.
Getting Started with Bundler
The basics of using Bundler are very trivial, you can be up and running in just a few minutes.
How to Install Ruby's Development Environment...
In the past, the Ruby “One-Click Installer” was the primary choice for installing Ruby on Windows. However, the One-Click Installer fell into disrepair and was eventually abandoned. Something new was needed, and thus, RubyInstaller was born.
What is Ruby?
New to Ruby? Or even to programming? Find out what Ruby really is (and isn't) and why you should (and shouldn't) use it.
Agile Development
The principles of Agile Development and how agile applies to Ruby on Rails.
How to Install and Use Ruby's Tk Toolkit
Directions of how to install the Tk GUI and its Ruby bindings on Windows, Linux and Mac OS X.
What's New in Rails 4?
Now that Rails 4 is out, let's see what's new.
How Does Ruby Compare to Python?
How do Ruby and Python compare in terms of features, form and function?
Be Notified of New Twitter Updates by IM
Be notified of Twitter updates by IM, using this Ruby script. It's a pain to switch to a Web browser every you want to check your Twitter account. This script solves that by sending you an instant message (IM) using the Jabber protocol when there's something new to see on Twitter.
Understanding 'String Literals' in Ruby
The basics of strings, string interpolation, single and double quotes, escape sequences and alternate string literal syntaxes.
Creating a URL Shortener in Rails
The following is a list of articles that will show you how to write, style and deploy a URL shortener (like TinyURL) application in Ruby on Rails.
Constant Variables
class="no-js" itemscope itemtype="http://schema.org/Article" > itemprop="description" >The speed of light
Boolean Operators
While simple boolean expressions will get you pretty far, you'll soon find yourself wanting to act on more than one condition. For that you'll need boolean operators.
Eval: Running Code on the Fly
Most non-compiled languages have some kind of eval function, which will take a string and execute it as code.
5 Must Know Features of the Ruby Language
If you're going to program in the Ruby language, there are some basic features you absolutely must know. Here are the Top 5.
Mapping Arrays
Iterating over arrays isn't the only trick up Ruby's sleeve. Having the ability to map arrays (and other enumerable collections) is a powerful feature.
Adding and Installing Gems from the Ruby Gems...
Learn to search the Ruby Gems repository to find gems to add and install to your library.
The Algorithm
Before we start coding, we take some time to look at the game of 2048.
Using Rack
In the previous article, you learned what Rack is. Now, it’s time to start using Rack and serve up some pages.
How Does Ruby Compare to the Java Programming...
What features do Ruby and the Java programming language share? How are they alike and how are they different?
Install Ruby on Windows
How to install the Ruby interpreter on the Windows operating system.
RVM and 'sudo'
RVM is great. However, there may be times where you must run Ruby scripts with RVM as root (or another user) via sudo.
Visual Tutorial: Installing Ruby on Windows
A visual walkthrough on installing Ruby on Windows. Page 4.
Adding Files to a Repository
How to add files to a Git repository.
What is Bundler?
Bundler is a gem dependency manager for Ruby.
Block Parameters and Yielding
class="no-js" itemscope itemtype="http://schema.org/Article" > itemprop="description" >Block parameters
NoSQL and Document Oriented Databases
Chances are, you've spent your entire database life with relational databases. Data gets organized into columns, and stored in rows. You manipulate data with SQL (Structured Query Language) and there's really no other way to do it. There are competing SQL servers out there (MySQL, SQLite, etc), but they all more or less operate in the same way. But there's much more out there than SQL databases, especially with all the new software in the past few years.
4 Ways Ruby is Better Than Your Programming...
A comparison of Ruby to other programming languages, including Perl, Java, Python and PHP.
25 Gem Commands for RubyGems
The gem command is one of the most used Ruby-related commands. This article shows 25 Gem Commands and their functions.
One Tree to Rule Them All
Some problems seem difficult, there are just too many things to consider and it's going to become a mess. However, if you analyze it, there's often a single data structure that will make the whole thing easier.
The 10 Fantastic Free Ways to Learn Ruby
Sometimes the old adage rings true: the best things in life are free. If you've wanted to learn a little Ruby, but haven't been able to fit a programming course into your budget, don't worry. There are a number of places on the Web to begin your learning, without sacrificing money or quality.
Net:SSH--Executing Programs with Net::SSH
Running programs with Net::SSH is simple enough. The Session object gives you two convenient methods with which to accomplish this task.
What is Cloud Computing?
What is cloud computing? Interviews with industry experts help us define cloud computing, software as service, platform as service and more.
An Introduction to Distributed Ruby
Distributed Ruby, or DRb, is a library that allows you to communicate with remote Ruby objects and programs, using TCP/IP network protocols.
What's a Regular Expression? Ruby Regular...
What is a regular expression and how do you use them in Ruby?
What is Sinatra?
Sinatra is a web framework. Simply put, it's a library that allows you to write web applications with a minimum of red tape.
Combining Arrays in Ruby
There are a number of ways to combine arrays in Ruby.
How to Use and Create Blocks in Ruby
How to use blocks in Ruby.
Creating Hashes from Arrays
How do you create hashes from tabular data? There are a few ways, but there's a way built into Ruby that fits onto a single line.
Mouse and Keyboard Input in Gosu
Games are, by definition, interactive. Gosu makes this interaction straightforward with a simple interface for detecting and reacting to key and mouse button presses.
Running the Ruby Profiler
Running the Ruby profiler to determine which methods are most expensive and which need to be optimized.
Base64 in Ruby
Base64 is a way to represent any data as ASCII data. Ruby provides a few handy functions to encode and decode Base64.
Rails Application Flow
When you program with any framework, you relinquish flow control in favor of convenience. The following is a description of what happens to a request as it passes through Ruby on Rails.
undefined method `to_sym' for nil:NilClass
Problem: Seemingly at random, you've encountered the error undefined method `to_sym' for nil:NilClass, or a similar error message for any method name other than to_sym.
Optional Method Parameters with Hashes
Using hashes to simulate optional named parameters in methods.
Finding Links
class="no-js" itemscope itemtype="http://schema.org/Article" > itemprop="description" >Most likely, you'll
CSV Example: Parsing CSV
A crash course on what CSV is, what it is used for and how it is parsed. A method for parsing CSV files using only Ruby's built-in string methods is presented and discussed.
Worked Example: Number Guessing Game
A number guessing game is written, and each of its features explored.
How to Display Your Ruby Version in Your Bash...
With RVM installed on your system, it's easy to have many versions of Ruby installed. And, especially if you switch between them often, it's easy to forget which Bash command prompt is using which Ruby version. You can solve this by putting your Ruby version in your Bash prompt.
Riding Shotgun with Sinatra
Now that you can write controller logic and views and Haml, you can start putting together some more complex application. There's one very annoying thing though: Sinatra does not reload its code whenever you make a change. If you make a change, you have to stop and restart the server. This is just an extra step and generally an annoyance. This where shotgun comes in.
What is Rack?
There’s a lot of talk about Rack , but unless you’re a framework author yourself, you rarely see it. So what is Rack? And why, as an application developer, should you care about it?
Cryptographic Hashes in Ruby
Generating cryptographic hashes in Ruby is quite easy. Ruby provides both a built in method and gives access to OpenSSL's hashing algorithms in most installations.
What's New in Ruby 1.9.1? -The Lambda Operator
Among the new features in release of Ruby 1.9.1 is the Lambda operator, a shortcut used to make nameless methods. Learn how to use this feature introduced in Ruby 1.9.1.
Embedding Images in Gosu Programs
Games can rarely run from a single file. Even if all of the game's code fits in a single file, there's bound to be image and sound data that accompanies it. Traditionally, to distribute a game, you zip the code and data up in a zip archive and distribute this file. However, sending a zip file isn't very transparent, and you often need a file hosting service to host the zip file.
Creating and Distributing Gems with Bundler
Creating Ruby gems has always been a bit of a pain. When you get right down to it, it's not a hard thing to do, but it's easy to forget how if you don't do it often enough. There are quite a few gems to help you write other gems, but if you're using Rails 3, there's already a gem on your system that does this: Bundler.
Installing Gosu
While Gosu does require native compilation, the developers thankfully require pre-compiled packages for all platforms. On Windows, Linux and OS X, Gosu can be installed with a single gem command.
Installing jRuby With RVM on OS X
As with most flavors of Ruby, the easiest, cleanest and least painful way to install jRuby is with RVM, the Ruby Version Manager. And although jRuby is different than MRI, the official Ruby interpreter, it can be installed just as easily, arguably easier.
Building Hashes
A hash is an associative array. Instead of using numerical indexes, any object (but typically symbols) can be used. They can be both a fast way to retrieve an object based on a key, and a convenient key/value store. There's no doubt, hashes are one of the most used types in Ruby.
extconf.rb:1:in `require': no such file to load...
Problem: You're trying to install a gem and you encounter an error reading no such file to load -- mkmf. This doesn't always occur, only when you're trying to install gems with native C code that must be compiled.
Load Vs. Require
You probably know about the 'require' method (yes, it is a method, it's not a keyword), but what about the 'load' method? What's so different about it?
Buttons and Submitting Forms
class="no-js" itemscope itemtype="http://schema.org/Article" > itemprop="description" >Buttons primarily
Installing Ruby on Rails on Windows
Installing Ruby, Rails and the few other things you'll need way always a pain on Windows. It's just not a very friendly environment for the task. But fear not, the guys at EngineYard have made RailsInstaller, and this task is braindead simple and will be done in minutes.
Net:SSH--Transferring Files with Net::SCP
SSH is not just for running commands, it's a general conduit for encrypted communications between two hosts. One common use for SSH is to transfer files using the SCP protocol over SSH. You can use SCP in your Ruby programs with the Net::SCP library, which is a supplement to Net::SSH.
Dynamic Method Calls
If you're coming from a compiled language, it's easy to think that method calls are like native function calls. This is simply not the case in Ruby.
How Use RMV to Install Ruby On OS X Snow Leopard
OS X has pretty easy access to a GCC development environment installed with XCode (an IDE and development
Quick Tip: Install Gems Faster
Some larger projects, especially Ruby on Rails, come with quite a bit of documentation. This is good, documentation is good, but the code that processes this documentation (RDoc) into HTML and ri format is not exactly speedy. On slower computers, or with larger projects, the time this takes becomes and annoyance.
What is the Difference Between alias and...
What is the difference between the alias keyword and the alias_method method? Why are they both there?
Constants in Ruby
Like just about every programming language every conceived, Ruby supports constants. A constant is a variable whose value cannot be changed. However, in Ruby, this has some caveats.
Ruby on Rails 3 Tutorial: Learn Rails by Example
Ruby on Rails 3 Tutorial: Learn Rails by Example by Michael Hartl is a hands on introduction to not only Ruby on Rails but all the related software and services many Rails developers use such as Git, Github, Heroku and RSpec. There are no long-winded discussions on theory or REST or MVC, each and every part of every chapter is a hands on exercise in building a Rails application. This book is recommended for anyone who prefers a hands on approach to learning.
AJAX With Sinatra
In this article we take a look at how to use jQuery and Sinatra to implement an AJAX interface.
What is ActiveRecord?
What is ActiveRecord? What can you do with it?
Installing Ruby on Rails on OS X
While Apple does include both Ruby and Ruby on Rails by default with OS X, you'll need to install newer versions. This is a bit of a process, but thankfully you'll only need to get through this just once.
Method Visibility
Method visibility is crucial to implement proper encapsulation. Ruby provides ways to not only hide instance variables, but to hide instance methods as well.
List of Rack Middleware
The following is a list of Rack middleware applications that come with the Rack gem. A brief description of each middleware is given.
Step 1: Scaffolding Posts
Without a framework like Rails, and particularly the scaffold generator, getting up and running with any project was a pain. You'd be doing a lot of configuring and planning and typing out all the methods to create blog posts and interact with the database. Rails does all this in just a few commands, and while it's not something you'll want to deploy right away, it does give you an excellent starting point.
Hello, Sinatra! Using Sinatra in Ruby
How to get started in Sinatra, including how to use actions, parameters, ERB and views.
Package Manager
A package manager is software on a Linux system that manages the other software installed on the system.
How Does Ruby Compare to PHP?
What are the similarities and dissimilarities between Ruby and PHP?
Ruby Challenge: Run Length Encoding
Run-length encoding is an obsolete but trivial compression algorithm. Not useful to know, but perfect for a programming challenge.
Overloading Operators
What does a + b mean? That all depends on what 'a' is. Ruby allows you to define a number of arithmetic operators and they're called on the left-hand side of any such expression.
How to Use the Twitter Gem for Ruby
Using the Twitter RubyGem, making API requests to Twitter is even easier than using the twitter method.
Rails Blog Tutorial - Allowing Comments
Part four of the Ruby on Rails blog tutorial shows you how to create a comments table to allow users to comment on your blog posts.
Using Git With Ruby on Rails
You don't have to use version control, but you should be. In the past, version control software has been large, clunky, required servers and really was only used when working in groups. But with Git, it's so easy that you really have no excuse, you should be using version control.
How to Install 'Git' on Windows
Installing command line tools such a Git on Windows is often difficult. Not only do you have to find a Windows port or attempt to compile the tool yourself from C source code, you also have to deal with the Windows command line. The Windows command line is, to say the least, a little lacking. Windows users are in luck here though, the MSysGit project solves both these problems.
Reference: Named Character Classes
A listing of the named character classes available to you in regular expressions in Ruby.
Basic Array Operations
Beyond creating arrays using literals, there are a few things you should know to get by with Arrays.
Serialization in Ruby: Marshal
Serializing an object is to convert an object to a byte stream and either store that object for future loading, or sending to another program to be loaded there. There are several common ways to serialize objects in Ruby. The Marshal module is used less often than the other methods, but it's included in the standard library.
Progress Bars with the ruby-progressbar Gem
How to use the ruby-progressbar gem to display progress bars on the command line.
Router Basics
The Ruby on Rails router is responsible for determining which action to run depending on the HTTP request type and URL passed by the web server.
Data Visualization
We've been organizing our game data in a tree, but a tree is kind of hard to visualize. Single objects and arrays you can simply puts to the terminal, but trees are a bit more difficult. Two methods are presented, one that prints the tree to the terminal and another that generates an image.
Getting and Printing Strings
How to read and print strings in Ruby.
Variables Declared in the Global Scope
I declared a variable in the global scope, and now I can't access it. What's going on here?
Working with Directories
Learning how to work with files is one of the first things new Ruby programmers learn. However, how to work with directories of files is something that's often skipped or only lightly touched upon. Ruby does have some powerful mechanisms for working with directories though.
Pseudocode
Pseudocode is example code in an imaginary language used to demonstrate an algorithm without writing a working implementation.
Automatically Following Followers on Twitter
Since the Twitter API makes it easy to do anything you can do on the website, writing a Ruby script to automatically follow followers is very simple.
Using rails.vim
Editing Rails projects in Vim effectively. Page 2.
Logging what Mechanize Does
class="no-js" itemscope itemtype="http://schema.org/Article" > itemprop="description" >In order to analyze
The Heroku Hacker's Guide by Randall Degges
comes in. The Heroku Hacker's Guide doesn't aim to be a complete reference (and since cloud computing
Everything You Need to Know About Variables
Variables are named references to objects in memory. Their several variants (local, instance, class, constant, etc) each have their own subtleties.
Class Variables
Class variables in Ruby are more or less as you'd expect form an object oriented language. However, Ruby throws you a curveball you can use to your advantage.
Making Digraphs in Ruby
Digraphs are extremely useful for hierarchical data visualization. However, they're not very easy to generate yourself. This is where Graphviz and the Graph gem come in.
Sorting Arrays
One of the most common tasks when dealing with arrays is to sort them. Luckily, Ruby makes this simple and flexible.
Step 3: Authentication with Devise
Before we get too invested in our blog, we need to set up some authentication. We'll be using the popular and capable Devise gem to handle authentication.
Step 2: Integrating a Wordpress Theme
The scaffold generator gave us something rather spartan, let's spruce this up by adapting a Wordpress theme to work with our shiny new blog.

©2015 About.com. All rights reserved.