Ruby’s case Statement Witout Comparison Value

Ruby’s case statement is genrally written with a comparison value behind it.

However, it is possible create a case statement without comparison value. In that case, it is equivalent in functionality to an if elsif else conditional.

case
when number % 3 == 0 && number % 5 == 0
  'FizzBuzz'
when number % 5 == 0
  'Buzz'
when number % 3 == 0
  'Fizz'
else
  number
end

Rubocop however, recommand to use an if expression:

Style/EmptyCaseCondition: Do not use empty case condition, instead use an if
expression.
if number % 3 == 0 && number % 5 == 0
  'FizzBuzz'
elsif number % 5 == 0
  'Buzz'
elsif number % 3 == 0
  'Fizz'
else
  number
end