DSL Study in ruby4

We use method.

events.rb

@a_target_sale = 0
@j_target_sale = 0
@a_sale = 0
@j_sale = 0

set_target_sales "set target_sales in America" do
  @a_target_sale = 50
end

set_target_sales "set target_sales in Japan" do
  @j_target_sale = 50
end

select_sales "select_sales in America" do
  @a_sale = 50
end

select_sales "select_sales in Japan" do
  @j_sale = 200
end

event "sales is enough in America" do
  @a_target_sale < @a_sale
end

event "sales is enough in Japan" do
  @j_target_sale < @j_sale
end

event "sales is soso in America" do
  @a_target_sale == @a_sale
end

event "sales is soso in Japan" do
  @j_target_sale == @j_sale
end

event "sales is not enough in America" do
  @a_target_sale > @a_sale
end

event "sales is not enough in Japan" do
  @j_target_sale > @j_sale
end

setup.rb

def event(description, &block)
  @events << {:description => description, :condition => block}
end

def select_sales(description, &block)
  @setups << {:description => description, :condition => block}
end

def set_target_sales(description, &block)
  @target_sales << {:description => description, :condition => block}
end

def each_event(&block)
  @events.each do |event|
    puts "----------START event: #{event[:description]}----------"
    block.call event
  end
end

def each_setup
  @setups.each do |setup|
    puts "#{setup[:description]}"
    setup[:condition].call
  end
end

def each_target_sale
  @target_sales.each do |target_sale|
    puts "START target_sale: #{target_sale[:description]}"
    target_sale[:condition].call
  end
end

act.rb

@events = []
@setups = []
@target_sales = []
load 'setup.rb'
load 'events.rb'

each_event do |event|
  each_target_sale
  each_setup
  puts "ALERT: #{event[:description]}" if event[:condition].call
end

ruby act.rb

Here are result.

----------START event: sales is enough in America----------
START target_sale: set target_sales in America
START target_sale: set target_sales in Japan
select_sales in America
select_sales in Japan
----------START event: sales is enough in Japan----------
START target_sale: set target_sales in America
START target_sale: set target_sales in Japan
select_sales in America
select_sales in Japan
ALERT: sales is enough in Japan
----------START event: sales is soso in America----------
START target_sale: set target_sales in America
START target_sale: set target_sales in Japan
select_sales in America
select_sales in Japan
ALERT: sales is soso in America
----------START event: sales is soso in Japan----------
START target_sale: set target_sales in America
START target_sale: set target_sales in Japan
select_sales in America
select_sales in Japan
----------START event: sales is not enough in America----------
START target_sale: set target_sales in America
START target_sale: set target_sales in Japan
select_sales in America
select_sales in Japan
----------START event: sales is not enough in Japan----------
START target_sale: set target_sales in America
START target_sale: set target_sales in Japan
select_sales in America
select_sales in Japan