DSL Study in ruby1

I implement basic DSL which Domain Specific Language

events.rb

def event(description)
  puts "ALERT: #{description}" if yield
end

# We can select data from database.
def select_sales
  puts "SELECT DATA"
  200
end

target_sales = 100

event "sales is enough" do
  target_sales <= select_sales
end

event "sales is not enough" do
  target_sales > select_sales
end

ruby events.rb

These are result.

SELECT DATA
ALERT: sales is enough
SELECT DATA