How To Stop A Loop In Ruby

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Loops are an essential part of any programming language as they allow you to repeat a block of code multiple times. However, there might be situations where you want to stop or break the loop based on certain conditions. In this blog post, we will explore different ways to stop a loop in Ruby.

1. Using the break keyword

The simplest way to stop a loop in Ruby is by using the break keyword. When Ruby encounters a break statement inside a loop, it immediately stops the execution of the loop and moves on to the next statement after the loop. You can use break in different looping constructs like while, until, for, and each.

Let’s look at an example using a while loop: 

count = 0
while count < 10
  puts "count: #{count}"
  if count == 5
    break
  end
  count += 1
end
puts "Loop exit at count: #{count}"

In this example, the loop will stop once the value of count reaches 5, and the output will be: 

count: 0
count: 1
count: 2
count: 3
count: 4
count: 5
Loop exit at count: 5

2. Using the next keyword

Another way to control loop execution in Ruby is by using the next keyword. While break stops the loop completely, next allows you to skip the remaining code in the current iteration and jump to the next one. This can be useful when you want to stop processing the current item and move to the next one based on a certain condition.

Let’s look at an example using a for loop: 

for num in 1..10
  if num % 2 == 0
    next
  end
  puts "Odd number: #{num}"
end

In this example, the loop will only output odd numbers, skipping even numbers using the next keyword: 

Odd number: 1
Odd number: 3
Odd number: 5
Odd number: 7
Odd number: 9

Conclusion

In this blog post, we learned how to stop a loop in Ruby using the break and next keywords. Both of these keywords provide you with greater control over the execution flow of your loops, allowing you to stop or skip iterations based on certain conditions.