deque-blog’s gists

deque-blog / fizz_buzz_kata_2016_tests_2.hs

Created December 31, 2016 16:33

	tests :: Test
	tests =
	let multiples_of_3_and_5 = [3 * 5, 2 * 3 * 5, 3 * 3 * 5]
	multiples_of_3 = [3, 1 * 3, 2 * 3, 3 * 3]
	multiples_of_5 = [5, 1 * 5, 2 * 5, 3 * 5]
	other_numbers = [0, 1, 2, 4]
	in TestList
	[ fizzBuzz `should_equal` "FizzBuzz" `for_all` multiples_of_3_and_5
	, fizzBuzz `should_equal` "Fizz" `for_all` multiples_of_3
	, fizzBuzz `should_equal` "Buzz" `for_all` multiples_of_5

deque-blog / fizz_buzz_kata_2016_tests_helpers.hs

Created December 31, 2016 16:35

	should_equal :: (Show t, Show a, Eq a) => (t -> a) -> a -> t -> Test
	should_equal underTest expected input =
	let label = "Expects " ++ show expected ++ " for " ++ show input
	in TestCase $ assertEqual label expected (underTest input)

	should_do_like :: (Show t, Show a, Eq a) => (t -> a) -> (t -> a) -> t -> Test
	should_do_like underTest refFct input
	= should_equal underTest (refFct input) input

	for_all :: (a -> Test) -> [a] -> Test

deque-blog / traversals_3_terrible_design.cpp

Last active January 8, 2017 14:18

	struct batch_options
	{
	bool m_with_minimum;
	bool m_with_average;
	bool m_with_variations;
	double m_limit;
	std::function<bool (stock_update const&)> m_filter;
	};

	struct batch_result

deque-blog / traversals_3_terrible_design_usage.cpp

Created January 8, 2017 15:01

	batch_result res = terrible_design(source, batch_options {
	true, true, true, 2.0,
	[](stock_update const& m) { return m.m_id == "A"; }
	});

deque-blog / traversals_3_filtering_parsing.cpp

Last active January 8, 2017 15:38

	template<typename Filter>
	auto read_stock_filtered_by(Filter filter) {
	return [filter] (auto const& source) {
	return source
	\| transformed(parse_message)
	\| filtered(filter)
	\| transformed(to(&stock::m_value));
	};
	}

deque-blog / traversals_3_filtering_parsing_usage.cpp

Last active January 8, 2017 15:32

	auto read_stock_by_id(std::string const& id) {
	return read_stock_filtered_by(equaling(id, on(&stock_update::m_id)));
	}

	//Assembling the algorithm, the source and the pipeline
	std::vector<std::string> fake_source = ... ;
	auto result = algorithm(read_stock_by_id("EUR")(fake_source));

deque-blog / traversals_3_multiple_pass_api.cpp

Created January 8, 2017 15:45

	template<typename Range>
	double extract_min_value(Range const& values);

	template<typename Range>
	double compute_average(Range const& values);

	template<typename Range>
	int count_big_variations(Range const& values);

deque-blog / traversals_3_multiple_pass_api_usage.cpp

Last active January 8, 2017 15:49

	auto read = read_stock_by_id("A");
	double min_val = extract_min_value(read(source));
	double avg_val = compute_average(read(source));
	int variation_count = count_big_variations(read(source));

deque-blog / traversal_3_average_step.cpp

Last active January 8, 2017 16:18

	struct RunningAverage
	{
	double m_value;
	int m_count;
	};

	struct GetAverage
	{
	RunningAverage operator()() const { return RunningAverage{ 0.0, 0 }; }
	RunningAverage operator()(RunningAverage const& avg, double value) const

deque-blog / traversal_3_minimum_step.cpp

Created January 8, 2017 16:08

	template<typename T>
	struct FindMinimum
	{
	T operator()() const { return std::numeric_limits<T>::max(); }
	T operator()(T const& current_min, T const& val) const
	{
	return std::min(current_min, val);
	}
	};