Pattern

ruby_pattern_matching.rb

def age_decider age
  case
  when age < 3
    "A baby"
  when age < 10
    "A kid"
  when age < 18
    "A teenager"
  when age > 65
    "A senior"
  else
    "An adult"
  end
end

test_output

$:ruby test.rb 
[1] pry(main)> age_decider 30
=> "An adult"
[2] pry(main)> age_decider 10
=> "A teenager"
[3] pry(main)> age_decider 2
=> "A baby"
[4] pry(main)> age_decider 4
=> "A kid"
[5] pry(main)> age_decider 99
=> "A senior"