Hello again! This lesson's topic is Ordered Hashes. Similar to Hashes, Ordered Hashes are data structures that store key-value pairs but maintain the order of insertion. Learning about Ordered Hashes enriches our set of tools for organized and efficient data manipulation. Today's goal is to work with Ordered Hashes using Ruby's built-in Hash
class, which maintains insertion order.
Hashes in Ruby are collections of key-value pairs, where each key is unique. They are versatile data structures, allowing various operations such as insertion, deletion, and retrieval based on the keys.
In Ruby all Hashes inherently maintain the order of elements based on their insertion sequence. The standard Hash now provides this behavior in newer Ruby versions, making a distinct data structure for sorting the items in order unnecessary.
To create an Ordered Hash, you simply need to create a standard Hash. For instance:
While Ruby's ordered hashes maintain elements in their insertion order, you may sometimes need to sort your hash according to custom criteria. You can accomplish this by using the sort
or sort_by
method, which allows you to sort hash elements based on specific logic.
Here's an example demonstrating how to sort an ordered hash by its keys in ascending order:
