Port Perl's truthy values to Ruby.

truthy.rb

#!/usr/bin/env ruby

class Object
  # The following are falsy: false, nil, 0, "", and empty arrays/hashes.
  # Anything else falls is truthy. This emulates Perl's truthiness.
  def truthy?
    if self.nil?
      return false
    elsif self.is_a? Fixnum
      return self != 0
    elsif self.is_a? String
      return !self.empty?
    elsif self.is_a? Array
      return self.length > 0
    elsif self.is_a? Hash
      return self.length > 0
    else
      return !!self
    end
  end
end

# Double-check truthy values
checks = [nil, 0, 1, '', 'test', 0.0, [], [nil], {}, {:a => 1}, false, true]
checks.each do |v|
  puts "#{v.inspect}.truthy?\t= #{v.truthy?}"
end