Ruby Gems

Understanding Ruby's defined? Keyword

Ruby's defined? keyword is an elegant way to check if a variable is defined or not and also to cache expensive operations. However, it's confusing, and a few gotchas await the new Rubyist. Now that I've had a few opportunities to play with it, here’s my shot at sparing you some of the confusion.

Ruby Gems 4 min read

What Does the Frozen String Literal Comment Do in Ruby?

Frozen strings not only prevent unintended modifications, but also reduce the overhead of the garbage collector by eliminating unnecessary memory allocations, thus improving application performance. This post explains the concept of freezing along with the magic comment frozen_string_literal.

Ruby Gems 7 min read

Speed Up Your Tests Using VCR Gem in Ruby

HTTP API requests can be slow. They're especially slow if you have to make them repeatedly in your tests. The VCR gem in Ruby speeds up your tests by recording the response the first time and replaying the same response for future runs. Let's understand how it works and how to use it.

Ruby Gems 5 min read

How to Generate Random Numbers in Ruby

This post covers the basics of random number generation in Ruby. As with everything in Ruby, there're multiple ways you could do it, with some approaches better than the other. We'll also explore generating random numbers in various formats as well as generating secure random numbers.

Ruby Gems 5 min read

Anonymous Block Forwarding in Ruby

In this post, we'll take a look at the anonymous block forwarding feature added in Ruby 3.1. It lets you replace your execute(&block) calls with execute(&). Not only it saves you from coming up with a variable (most likely blk), it also looks pretty sweet. I dig it.

Ruby Gems 2 min read

What is __FILE__ in Ruby?

You must have come across the mysterious term __FILE__ while reading Ruby code. It's a magic variable that returns the name of the current file. This short post shows a few different use cases that I found while reading the Rails source code.

Ruby Gems 1 min read

How to Remove Whitespace from a String in Ruby

Often, you want to sanitize a string variable by removing all leading and trailing whitespaces around it. This is usually needed when you receive the string input from a user or an external source. This post shows you how.

Ruby Gems 2 min read

Nested Modules in Ruby

There are two different ways to define nested modules in Ruby. This post explains them both along with the differences between them and how to decide which one to use. We will also learn about the `Module.nesting` method, which returns the list of nesting for a module.

Ruby Gems 3 min read

How self Keyword Works in Ruby

Ruby's self keyword can be pretty confusing to understand, especially if you're new to Ruby. Not understanding it often leads to subtle programming bugs that can be difficult to debug. This post explains how it works under common, everyday situations.

Ruby Gems 2 min read

Understanding Blocks and the Difference in Proc and Lambda

Update: I've since revised, polished and published a much more in-depth post on this topic, check it out here: Blocks, Procs, and Lambdas:

Ruby Gems 4 min read

Ruby Shortcut to Call a Method with Each Array Item as Parameter

As a Ruby programmer, you probably know the &: shortcut to call a method on each item in an array. For example, this snippet will

Ruby Gems 2 min read

class_eval vs. instance_eval in Ruby

This post explains the difference between class_eval and instance_eval methods in Ruby. If you keep getting confused between them when reading or writing

Ruby Gems 3 min read