module Quarry

  module Grammar

    # = Assert Nomenclature
    #
    # Some people prefer TDD over BDD so we also provide an 
    # assertion-based nomenclature.
    #
    module Assert

      # Assert a operational relationship.
      #
      #   4.assert == 3
      #
      def assert
        return Expectation.new(self, :backtrace=>caller)
      end

      # Assert not an operational relationship.
      # Read it as "assert not".
      #
      #   4.assert! == 4
      #
      # AUHTOR'S NOTE: This method would not be necessary
      # if Ruby would allow +!=+ to be define as a method,
      # or at least +!+ as a unary method.
      #
      def assert!
        return Expectation.new(self, :negate=>true, :backtrace=>caller)
      end

      # Same as #assert!.
      #
      # 4.refute == 4  #=> Assertion Error
      #
      alias_method :refute, :assert!

    end

  end

  class ::Object #:nodoc:
    include Grammar::Assert
  end

end