require './safetyblanket'

class Cruft
  extend SafetyBlanket

  int def foo(arg)
    puts arg
    arg
  end
  
  char def first_letter(arg)
    puts arg[0]
    arg[0]
  end
  
  void def null_factory(arg)
    puts arg
    nil
  end
end

cruft = Cruft.new
cruft.foo 37
cruft.null_factory "🏭"
cruft.first_letter "pie"
cruft.foo "monkey"

37
ABBA
🏭
p
20
monkey
(eval):10:in `foo': foo returned String instead of Fixnum (RuntimeError)
        from example.rb:59:in `<main>'

module SafetyBlanket
  require 'set'

  def set(symbol)
    safetyblanketize symbol, Set
  end
  
  def Palindrome(symbol)
    safetyblanketize symbol, String do |str|
      str == str.reverse
    end
  end
end