gistfile1.rb

require 'clean_assert'

def add_drinking_person(name, age)
  assert / "name != nil" / "not name.empty?" / "age >= 21"
  puts "Adding '#{name}' of age #{age} to the list of drinkers"
  # And some code to do it...
end

add_drinking_person("Niclas", 17)
# Gives:
# RuntimeError: Assertion 'age >= 21' not satisfied in main#add_drinking_person