Custom Enumerable Project
December 27, 2025 ยท View on GitHub
This repository complements the Custom Enumerables Project in the Ruby Course for The Odin Project. The goal of this project is to reimplement common methods used frequently through the enumerables module with objects like arrays and hashes. This project will also familiarize you with how to work with blocks and procs. Some starter code and specs are provided to validate the correctness of your solutions.
Installation
First, clone this repository with
git clone git@github.com:TheOdinProject/custom_enumerable_project.git
Then, navigate into the folder through your command line with
cd custom_enumerable_project
and install the dependencies using the command
Note
If you get a Ruby version error, it's recommended to update your ruby installation. Alternatively, you can change the local ruby version to your installed version if your version is not too behind from output of rbenv local. (to check your installed version: ruby -v)
bundle install
Getting Started
You will add new methods to the Enumerable module in lib/my_enumerables.rb. Before you implement a method, go to the corresponding spec file and watch the test fail by running
bundle exec rspec <spec_file>
You can find the associated spec file in the methods section. Then, add the method to the enumerable module. Run the tests again using the same command until they pass.
Example
As an example, before you start implementing the my_each method, run
bundle exec rspec spec/my_each_spec.rb
to see that the test fails as expected.
Once you implement it, like so:
# lib/my_enumerables.rb
class Array
def my_each
# Complete code
end
end
run the command
bundle exec rspec spec/my_each_spec.rb
again to see if your code is correct or not.
Methods
The following table has the methods you will need to implement along with their associated specs, as outlined in the project instructions. The methods in the Enumerable module only need to work with Arrays, but you can challenge yourself and try to make them work for Hashes as well.
| Method | Spec File | Notes |
|---|---|---|
Array#my_each | spec/my_each_spec.rb | You will define my_each on the Array class in lib/my_enumerables.rb |
Enumerable#my_each_with_index | spec/my_each_with_index_spec.rb | |
Enumerable#my_select | spec/my_select_spec.rb | |
Enumerable#my_all? | spec/my_all_spec.rb | |
Enumerable#my_any? | spec/my_any_spec.rb | |
Enumerable#my_none? | spec/my_none_spec.rb | |
Enumerable#my_count | spec/my_count_spec.rb | |
Enumerable#my_map | spec/my_map_spec.rb | |
Enumerable#my_inject | spec/my_inject_spec.rb |