23 #include <meta/meta.hpp>
32 namespace seqan3::detail
35 #if SEQAN3_WORKAROUND_GCC7_AND_8_CONCEPT_ISSUES
37 SEQAN3_CONCEPT variant_guard_pseudoalphabet = requires { requires seqan3::alphabet_size<t> > 0; };
38 #endif // SEQAN3_WORKAROUND_GCC7_AND_8_CONCEPT_ISSUES
41 template <
typename other_t,
typename ... alternative_types>
42 inline constexpr
bool variant_general_guard =
43 (!
std::same_as<other_t, alphabet_variant<alternative_types...>>) &&
47 #if SEQAN3_WORKAROUND_GCC7_AND_8_CONCEPT_ISSUES
48 && variant_guard_pseudoalphabet<other_t>
49 #endif // SEQAN3_WORKAROUND_GCC7_AND_8_CONCEPT_ISSUES
53 template <
typename lhs_t,
typename rhs_t,
bool lhs_rhs_switched,
typename ... alternative_types>
54 inline constexpr
bool variant_comparison_guard =
55 (instantiate_if_v<lazy<weakly_equality_comparable_with_trait, rhs_t, alternative_types>,
56 (
std::same_as<lhs_t, alphabet_variant<alternative_types...>>) &&
57 (variant_general_guard<rhs_t, alternative_types...>) &&
58 !(lhs_rhs_switched && is_type_specialisation_of_v<rhs_t, alphabet_variant>)
122 template <
typename ...alternative_types>
124 requires (detail::writable_constexpr_alphabet<alternative_types> && ...) &&
126 (
sizeof...(alternative_types) >= 2)
130 (static_cast<size_t>(alphabet_size<alternative_types>) + ...),
137 (static_cast<size_t>(alphabet_size<alternative_types>) + ...),
143 using alternatives = meta::list<alternative_types...>;
145 static_assert(
std::same_as<alternatives, meta::unique<alternatives>>,
146 "All types in a alphabet_variant must be distinct.");
158 using seqan3_required_types =
type_list<alternative_types...>;
161 using seqan3_recursive_required_types =
163 detail::transformation_trait_or_t<detail::recursive_required_types<alternative_types>,
171 template <
typename alternative_t>
174 return detail::type_in_pack_v<alternative_t, alternative_types...>;
193 template <typename alternative_t>
198 detail::transformation_trait_or_t<detail::recursive_required_types<alternative_t>,
type_list<>>>) &&
222 template <
typename indirect_alternative_t>
224 requires ((detail::instantiate_if_v<
225 detail::lazy<std::is_convertible, indirect_alternative_t, alternative_types>,
226 detail::variant_general_guard<indirect_alternative_t, alternative_types...>> || ...))
233 detail::implicitly_convertible_from<indirect_alternative_t>>>(rhs)));
250 template <
typename indirect_alternative_t>
252 requires ((!(detail::instantiate_if_v<
253 detail::lazy<std::is_convertible, indirect_alternative_t, alternative_types>,
254 detail::variant_general_guard<indirect_alternative_t, alternative_types...>> || ...)) &&
255 (detail::instantiate_if_v<
256 detail::lazy<std::is_constructible, alternative_types, indirect_alternative_t>,
257 detail::variant_general_guard<indirect_alternative_t, alternative_types...>> || ...))
262 detail::constructible_from<indirect_alternative_t>>>(rhs)));
274 template <
typename indirect_alternative_t>
276 requires (detail::variant_general_guard<indirect_alternative_t, alternative_types...> &&
281 using alternative_t = meta::front<meta::find_if<alternatives, detail::assignable_from<indirect_alternative_t>>>;
282 alternative_t alternative{};
292 template <
size_t index>
297 static_assert(index <
alphabet_size,
"The alphabet_variant contains less alternatives than you are checking.");
298 return (
to_rank() >= partial_sum_sizes[index]) && (
to_rank() < partial_sum_sizes[index + 1]);
305 template <
size_t index>
308 return convert_impl<index, true>();
314 template <
size_t index>
317 return convert_impl<index, false>();
327 template <
typename alternative_t>
333 constexpr
size_t index = meta::find_index<alternatives, alternative_t>::value;
334 return is_alternative<index>();
341 template <
typename alternative_t>
347 constexpr
size_t index = meta::find_index<alternatives, alternative_t>::value;
348 return convert_impl<index, true>();
354 template <
typename alternative_t>
360 constexpr
size_t index = meta::find_index<alternatives, alternative_t>::value;
361 return convert_impl<index, false>();
385 template <
typename alphabet_variant_t,
typename indirect_alternative_type>
386 friend constexpr
auto operator==(alphabet_variant_t
const lhs, indirect_alternative_type
const rhs) noexcept
388 indirect_alternative_type,
390 alternative_types...>,
393 using alternative_t =
395 detail::weakly_equality_comparable_with_<indirect_alternative_type>>>;
396 return lhs.template is_alternative<alternative_t>() && (lhs.template convert_unsafely_to<alternative_t>() == rhs);
400 template <
typename alphabet_variant_t,
typename indirect_alternative_type>
401 friend constexpr
auto operator!=(alphabet_variant_t
const lhs, indirect_alternative_type
const rhs) noexcept
403 indirect_alternative_type,
405 alternative_types...>,
408 return !(lhs == rhs);
412 template <
typename alphabet_variant_t,
typename indirect_alternative_type,
typename =
void>
413 friend constexpr
auto operator==(indirect_alternative_type
const lhs, alphabet_variant_t
const rhs) noexcept
415 indirect_alternative_type,
417 alternative_types...>,
424 template <
typename alphabet_variant_t,
typename indirect_alternative_type,
typename =
void>
425 friend constexpr
auto operator!=(indirect_alternative_type
const lhs, alphabet_variant_t
const rhs) noexcept
427 indirect_alternative_type,
429 alternative_types...>,
443 template <
size_t index,
bool throws>
444 constexpr
auto convert_impl() const noexcept(!throws) -> meta::at_c<alternatives, index>
446 static_assert(index <
alphabet_size,
"The alphabet_variant contains less alternatives than you are checking.");
447 using alternative_t = meta::at_c<alternatives, index>;
449 if constexpr (
throws)
451 if (!is_alternative<index>())
467 static constexpr
std::array<
rank_type,
sizeof...(alternative_types) + 1> partial_sum_sizes = []() constexpr
469 constexpr
size_t N =
sizeof...(alternative_types) + 1;
472 for (
size_t i = 1u; i < N; ++i)
473 partial_sum[i] += partial_sum[i-1];
490 auto assign_rank_to_char = [](
auto alternative,
size_t rank) constexpr
495 auto assign_value_to_char = [assign_rank_to_char] (
auto alternative,
auto & value_to_char,
auto & value) constexpr
497 using alternative_t =
std::decay_t<decltype(alternative)>;
498 for (
size_t i = 0u; i < seqan3::alphabet_size<alternative_t>; ++i, ++value)
499 value_to_char[value] = assign_rank_to_char(alternative, i);
509 ((assign_value_to_char(alternative_types{}, value_to_char, value)),...);
511 return value_to_char;
518 template <
size_t index,
typename alternative_t>
520 requires holds_alternative<alternative_t>()
522 static constexpr
rank_type rank_by_index_(alternative_t const & alternative) noexcept
524 return partial_sum_sizes[index] + static_cast<rank_type>(
seqan3::to_rank(alternative));
531 template <
typename alternative_t>
533 requires holds_alternative<alternative_t>()
535 static constexpr
rank_type rank_by_type_(alternative_t const & alternative) noexcept
537 constexpr
size_t index = meta::find_index<alternatives, alternative_t>::value;
538 return rank_by_index_<index>(alternative);
550 constexpr
size_t table_size = detail::size_in_values_v<char_type>;
554 for (
size_t i = 0u; i < table_size; ++i)
556 char_type chr = static_cast<char_type>(i);
557 bool there_was_no_valid_representation{
true};
559 meta::for_each(alternatives{}, [&] (
auto && alt)
563 if (there_was_no_valid_representation && char_is_valid_for<alt_type>(chr))
565 there_was_no_valid_representation =
false;
570 if (there_was_no_valid_representation)
571 char_to_rank[i] = rank_by_type_(
assign_char_to(chr, meta::front<alternatives>{}));
578 static constexpr
bool char_is_valid(
char_type const chr) noexcept
580 bool is_valid{
false};
582 meta::for_each(alternatives{}, [&] (
auto && alt)