add single-word boolean methods to String

string.rb

class String
  # alias the method_missing method chain so that we can use single-word booleans
  # for example, we can do things like "standard".standard? which will give us true
  # obviously this is most suited for cases where you have a variable with a value from a known set of values
  def method_missing_with_single_word_booleans(method_name, *args, &block)
    return method_missing_without_single_word_booleans(method_name, *args, &block) unless method_name.to_s =~ /^(\w+)\?$/
    self == $1
  end
  alias_method_chain :method_missing, :single_word_booleans
end

Already a part of Rails in the form of ActiveSupport::StringInquirer