Fun with Ruby's BEGIN and END blocks

another_required_file.rb

puts "[3] Inside 'another_required_file.rb'"

BEGIN {
  puts "[2] BEGIN inside 'another_required_file.rb'"
}

# END blocks will execute at the end of the program, in reverse order to when
# they're encountered
END {
  puts "[5] END inside 'another_required_file.rb'"
}

app.rb

# http://ruby-doc.org/docs/keywords/1.9/Object.html#method-i-END

$LOAD_PATH << File.dirname(__FILE__)
require 'required_file'
require 'another_required_file'
puts "[4] End of 'app.rb'"

required_file.rb

puts "[1] Inside 'required_file.rb'"

BEGIN {
  puts "[0] BEGIN inside 'required_file.rb'"
}

END {
  puts "[6] END inside 'required_file.rb'"
}