Ruby Convert List to Hash

1. Introduction

In Ruby, you may occasionally need to convert a list (an array) to a hash. This conversion can be handy when you need to create a more complex data structure from a simple list, for instance, to index elements or to map additional information to each item. This blog post will demonstrate how to turn a list into a hash in Ruby.

A list in Ruby is known as an array, a collection of ordered items. A hash, sometimes referred to as a dictionary in other programming languages, is a collection of key-value pairs. It's a data structure that offers a way of storing data so that it can be accessed quickly by keys.

2. Program Steps

1. Define the list (array) to be converted into a hash.

2. Decide on the structure of the hash. The elements of the array could become the keys or the values, or the array could be an array of pairs.

3. Convert the list to a hash using the appropriate method based on the chosen structure.

4. Output the new hash.

3. Code Program

# Step 1: Define the list (array) to be converted
list = [['first_name', 'John'], ['last_name', 'Doe'], ['age', 30]]
# Step 2: The structure is an array of pairs, where the first item is the key and the second is the value
# Step 3: Convert the list to a hash
hash = Hash[list]
# hash now contains the data from the list structured as a hash

Output:

{"first_name"=>"John", "last_name"=>"Doe", "age"=>30}

Explanation:

1. list is the array with sub-arrays where each sub-array is a pair corresponding to a hash key and value.

2. The array structure is chosen to be an array of pairs, which can be directly converted to a hash.

3. Hash[list] is Ruby's built-in method that transforms an array of key-value pair arrays into a hash.

4. hash is the resulting hash from the conversion, which contains the same key-value pairs as the original list of pairs.