Ruby is amazing... Try to do this in Java (it is possible, but not in so concise and readable way). Speaking of tests, is there any known way to get test/unit report the results in XML, a la Ant Junit runner? Other markup easily convertible to HTML would do just as fine. <code> require 'test/unit' class ClassUnderTest def square(i) i * i end end class ParaTest < Test::Unit::TestCase # test methods are added dynamically to this class later in this file end expectedResults = {-5 => 25, -1 => 1, 0 => 0, 1 => 1, 10 => 100, 999999999 => 999999998000000001} expectedResults.each_pair do |parameter, expectedResult| ParaTest.module_eval <<-EOL def testSquareOf#{parameter.to_s.sub('-', 'Minus')} assert_equal #{expectedResult}, ClassUnderTest.new.square(#{parameter}) end EOL end </code> Best regards, Alexey Verkhovsky