Ranges in Ruby Language

Ranges in Ruby are a versatile and powerful feature that allow you to express a range of values between a start

and end point. They are commonly used for tasks such as iterating over a sequence of numbers, selecting a portion of an array, and checking if a value falls within a certain range. In this post, we’ll explore the basics of ranges in Ruby, their syntax, and various use cases.

Creating Ranges

In Ruby, you can create a range using two dots .. or three dots .... The two-dot range includes both the start and end values, while the three-dot range includes the start value but excludes the end value.

Inclusive Range (..)

inclusive_range = 1..5
# This range includes 1, 2, 3, 4, and 5

Exclusive Range (…)

exclusive_range = 1...5
# This range includes 1, 2, 3, and 4 (excludes 5)

Range as a Sequence

Ranges are often used to create sequences of numbers. You can iterate over these sequences, making your code more concise and readable.

(1..5).each do |num|
  puts num
end

# Output:
# 1
# 2
# 3
# 4
# 5

Range as a Condition

Ranges are also useful for checking if a value falls within a specific range.

temperature = 25

if (0..32).include?(temperature)
  puts "It's freezing!"
elsif (33..70).include?(temperature)
  puts "It's comfortable."
else
  puts "It's hot outside!"
end

Range with Arrays

You can use ranges to select a portion of an array, which is a common operation in Ruby.

numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
selected_numbers = numbers[2..5]
# selected_numbers will contain [3, 4, 5, 6]

Custom Objects

Ranges are not limited to integers; you can use custom objects as well, as long as they define the <=> (spaceship) operator to compare values.

date_range = Date.new(2023, 1, 1)..Date.new(2023, 12, 31)

Infinite Ranges

Ruby allows you to create infinite ranges, which can be useful for lazy enumeration.

infinite_range = 1..Float::INFINITY
infinite_range.each do |number|
  break if number > 10
  puts number
end