In this guide we’ll examine how to implement the sort_by method in order to sort a collection of Ruby struct objects by a specific attribute.
Summary
Build a method that iterates over a collection of struct objects and sort them by a specific attribute.
Exercise File
Exercise Description
Given the following array of structs:
Invoice = Struct.new(:name, :total, :category)
google = Invoice.new('Google', 500, 'Marketing')
amazon = Invoice.new('Amazon', 1000, 'eCommerce')
yahoo = Invoice.new('Yahoo', 300, 'Marketing')
invoices = [google, amazon, yahoo]
Build out a method that sorts the objects by their total values.
Expected Output
invoices.first.name # 'Amazon' invoices.last.name # 'Yahoo'
Real World Usage
Ruby’s sort_by method is a powerful, but underused method, that allows you to build custom sorting behavior. This is a feature you will be asked to build out on a regular basis as a Ruby developer.
Solution
Can be found on the solutions branch on github.
