If you are coming from using python, then you will be used to using a lot of if...elif...else statements to catch conditions in variables. Sometimes this can be tedious - in Ruby it is easier to use case statements.
Let’s assume that you are checking for ages of people and want to classify them according to their age (it might be a sceranio of runners in a race and you want to find out who won each age range). Here you can use when.
group = ""
age = gets.chomp.to_i
case age
when 0..17
group = "Under 18s"
when 18..25
group = "18s to 25s"
when 26..30
group = "26s to 30"
when 30..Float::INFINITY
group = "Over 30s"
end
puts group
This allows us to somewhat simplify the conditions that might come about from different ages.