gatchamix’s gists

gatchamix / is_constexpr.cpp

Last active August 27, 2021 06:25

is_constexpr macro to determine whether a given expression can be assigned to a constexpr variable or not

	#include <utility>
	#include <string>
	#include <string_view>

	using namespace std::literals;

	//

	template <class F, class... Args,
	class = decltype(std::declval<F&&>()(std::declval<Args&&>()...))>

gatchamix / cows_bulls.cpp

Created November 17, 2017 18:48

Implementation of Cows and Bulls game

	#include <cstdint>
	#include <algorithm>
	#include <tuple>

	template <class... Ts>
	auto constexpr persist(Ts volatile... ts)
	{ std::tuple{ ts... }; }

	auto constexpr hamming_weight(std::uint16_t const mask,
	std::uint16_t const value)

gatchamix / is_constexpr.cpp

Created December 12, 2017 10:43

Improved is_constexpr checking macro (by quicknir)

	#include <utility>
	#include <string>
	#include <string_view>

	using namespace std::literals;

	//

	auto constexpr checker(...) {}

gatchamix / auto_assert.cpp

Created July 20, 2018 16:14

macro to automatically select 'static_assert' where possible, default to 'assert' otherwise

	#include <cassert>

	#define auto_assert(...) \
	[](auto expression) \
	{ \
	if constexpr (noexcept(expression())) \
	{ static_assert(expression()); } \
	else \
	{ assert(expression()); } \
	} \

gatchamix / matrix17.cpp

Last active July 25, 2018 21:14

simple matrix container using C++17 (original idea courtesy of jdmarsh)

	#include <utility>
	#include <cstddef>
	#include <array>
	#include <type_traits>

	//

	template <class T, std::size_t Rows, std::size_t Cols = Rows>
	struct matrix
	{

gatchamix / tuple2a.cpp

Last active July 24, 2019 15:55

simple tuple container using C++2a

gatchamix / constant.cpp

Created July 28, 2018 02:44

compile-time constant wrapper

gatchamix / insertion_sort.cpp

Created August 15, 2018 23:34

fast insertion sort for non-type template parameter packs in C++2a

	static auto constexpr less = [](auto&& l, auto&& r) { return l < r; };
	static auto constexpr less_equal = [](auto&& l, auto&& r) { return l <= r; };
	static auto constexpr greater = [](auto&& l, auto&& r) { return l > r; };
	static auto constexpr greater_equal = [](auto&& l, auto&& r) { return l <= r; };

	//

	template <template <auto...> class C, auto... Vs, class Fn>
	auto constexpr sort(C<Vs...> in, Fn)
	{

gatchamix / is_constexpr.cpp

Created September 18, 2018 10:13

solutions for determining if an expression meets the standard's definition of constant-expression

	#include <utility>
	#include <string>
	#include <string_view>
	#include <type_traits>

	using namespace std::literals;

	#define version 17

	// C++11 solution

gatchamix / has_member_function.cpp

Last active October 12, 2018 09:06

faux-function to determine whether a class/struct has a function (optionally checking for a specific type signature)