refactor: enhance group module

CMakeLists.txt

@@ -18,7 +18,7 @@ if (NOT CMAKE_BUILD_TYPE)
   set(CMAKE_BUILD_TYPE Release)
 endif()
 
-add_compile_options(-Wall -Wextra)
+add_compile_options(-Wall -Wextra -g)
 
 # TODO: enabled by LTO option
 if (CMAKE_CXX_COMPILER_ID STREQUAL "Clang")

src/core/CMakeLists.txt

@@ -38,6 +38,7 @@ add_library(klotski::core ALIAS klotski_core)
 
 if (KLSK_DEV_MODE)
   add_executable(klotski_core_bin main.cc)
+  target_compile_options(klotski_core_bin PRIVATE -fno-rtti -fno-exceptions)
   target_link_libraries(klotski_core_bin PRIVATE klotski::core)
 endif()
 

src/core/group/group.h

@@ -150,9 +150,12 @@
 
 #pragma once
 
-#include "raw_code/raw_code.h"
-#include "short_code/short_code.h"
-#include "common_code/common_code.h"
+#include <mutex>
+
+#include "ranges/ranges_fwd.h"
+#include "raw_code/raw_code_fwd.h"
+#include "short_code/short_code_fwd.h"
+#include "common_code/common_code_fwd.h"
 
 #include "internal/constant/group.h"
 #include "internal/constant/group_union.h"
@@ -195,13 +198,13 @@ public:
     using Groups = std::vector<Group>;
 
     /// Get all groups under the current type id.
-    [[nodiscard]] constexpr Groups groups() const; // TODO: constexpr not support `std::vector`
+    [[nodiscard]] Groups groups() const;
 
     /// Get all klotski cases under the current type id.
     [[nodiscard]] cases::RangesUnion cases() const;
 
     /// Get the group instance with the specified pattern id.
-    [[nodiscard]] constexpr std::optional<Groups> groups(uint_least16_t pattern_id) const;
+    [[nodiscard]] std::optional<Groups> groups(uint_least16_t pattern_id) const;
 
     // ------------------------------------------------------------------------------------- //
 
@@ -240,23 +243,21 @@ private:
     // ------------------------------------------------------------------------------------- //
 };
 
-// TODO: using macro for all likely-class
-
+static_assert(sizeof(GroupUnion) == 1);
 static_assert(std::is_standard_layout_v<GroupUnion>);
 static_assert(std::is_trivially_copyable_v<GroupUnion>);
-static_assert(!std::is_default_constructible_v<GroupUnion>);
-static_assert(std::is_trivially_destructible_v<GroupUnion>);
-static_assert(std::is_nothrow_destructible_v<GroupUnion>);
+static_assert(std::has_unique_object_representations_v<GroupUnion>);
 
-static_assert(std::is_nothrow_copy_assignable_v<GroupUnion>);
-static_assert(std::is_nothrow_move_assignable_v<GroupUnion>);
-static_assert(std::is_nothrow_copy_constructible_v<GroupUnion>);
-static_assert(std::is_nothrow_move_constructible_v<GroupUnion>);
+} // namespace klotski::group
 
-static_assert(std::is_trivially_copy_assignable_v<GroupUnion>);
-static_assert(std::is_trivially_move_assignable_v<GroupUnion>);
-static_assert(std::is_trivially_copy_constructible_v<GroupUnion>);
-static_assert(std::is_trivially_move_constructible_v<GroupUnion>);
+template <>
+struct std::hash<klotski::group::GroupUnion> {
+    constexpr std::size_t operator()(const klotski::group::GroupUnion &gu) const noexcept {
+        return std::hash<uint_fast8_t>{}(gu.unwrap());
+    }
+};
+
+namespace klotski::group {
 
 class Group {
 public:
@@ -274,7 +275,7 @@ public:
         Horizontal = 1, // horizontal self-symmetry
         Centro = 2, // centrosymmetric
         Vertical = 3, // vertical self-symmetry
-        Ordinary = 4, // non self-symmetric
+        Ordinary = 4, // non-self-symmetric
     };
 
     // ------------------------------------------------------------------------------------- //
@@ -342,7 +343,7 @@ public:
     // ------------------------------------------------------------------------------------- //
 
     /// Get the group in string form.
-    [[nodiscard]] std::string to_string() const;
+    [[nodiscard]] KLSK_INLINE std::string to_string() const;
 
 #ifndef KLSK_NDEBUG
     /// Output group info only for debug.
@@ -368,8 +369,21 @@ private:
     // ------------------------------------------------------------------------------------- //
 };
 
+static_assert(sizeof(Group) == 4);
 static_assert(std::is_standard_layout_v<Group>);
 static_assert(std::is_trivially_copyable_v<Group>);
+static_assert(std::has_unique_object_representations_v<Group>);
+
+} // namespace klotski::group
+
+template <>
+struct std::hash<klotski::group::Group> {
+    constexpr std::size_t operator()(const klotski::group::Group &g) const noexcept {
+        return std::hash<uint32_t>{}(std::bit_cast<uint32_t>(g));
+    }
+};
+
+namespace klotski::group {
 
 class CaseInfo {
 public:
@@ -394,7 +408,7 @@ public:
     // ------------------------------------------------------------------------------------- //
 
     /// Get case info in string form.
-    [[nodiscard]] std::string to_string() const;
+    [[nodiscard]] KLSK_INLINE std::string to_string() const;
 
 #ifndef KLSK_NDEBUG
     /// Output case info only for debug.
@@ -416,8 +430,21 @@ private:
     // ------------------------------------------------------------------------------------- //
 };
 
+static_assert(sizeof(CaseInfo) == 8);
 static_assert(std::is_standard_layout_v<CaseInfo>);
 static_assert(std::is_trivially_copyable_v<CaseInfo>);
+static_assert(std::has_unique_object_representations_v<CaseInfo>);
+
+} // namespace klotski::group
+
+template <>
+struct std::hash<klotski::group::CaseInfo> {
+    constexpr std::size_t operator()(const klotski::group::CaseInfo &info) const noexcept {
+        return std::hash<uint64_t>{}(std::bit_cast<uint64_t>(info));
+    }
+};
+
+namespace klotski::group {
 
 class GroupCases {
 public:
@@ -491,12 +518,10 @@ private:
 
 } // namespace klotski::group
 
-#include "internal/type_id.inl"
-#include "internal/group_union.inl"
-
 #include "internal/group.inl"
-#include "internal/group_mirror.inl"
-
 #include "internal/group_cases.inl"
+#include "internal/group_union.inl"
+
+#include "internal/mirror.inl"
+#include "internal/type_id.inl"
 #include "internal/case_info.inl"
-#include "internal/hash.inl"

src/core/group/group_fwd.h

@@ -0,0 +1,15 @@
+/// Klotski Engine by Dnomd343 @2024
+
+#pragma once
+
+#include "internal/constant/group.h"
+#include "internal/constant/group_union.h"
+
+namespace klotski::group {
+
+class Group;
+class CaseInfo;
+class GroupCases;
+class GroupUnion;
+
+} // namespace klotski::group

src/core/group/internal/case_info.inl

@@ -4,25 +4,41 @@
 
 namespace klotski::group {
 
-inline std::ostream& operator<<(std::ostream &out, CaseInfo self) {
+// ----------------------------------------------------------------------------------------- //
+
+constexpr Group CaseInfo::group() const {
+    return group_;
+}
+
+constexpr uint32_t CaseInfo::case_id() const {
+    return case_id_;
+}
+
+// ----------------------------------------------------------------------------------------- //
+
+KLSK_INLINE_H std::string CaseInfo::to_string() const {
+    // TODO: benchmark of format `{}-{}{}-{}`
+    return std::format("{}-{}", group_.to_string(), case_id_);
+}
+
+#ifndef KLSK_NDEBUG
+inline std::ostream& operator<<(std::ostream &out, const CaseInfo self) {
     out << self.to_string();
     return out;
 }
+#endif
 
 constexpr auto operator==(const CaseInfo &lhs, const CaseInfo &rhs) {
     return lhs.group_ == rhs.group_ && lhs.case_id_ == rhs.case_id_;
 }
 
-inline std::string CaseInfo::to_string() const {
-    return std::format("{}-{}", group_.to_string(), case_id_);
-}
+// ----------------------------------------------------------------------------------------- //
 
-constexpr Group CaseInfo::group() const {
-    return group_;
-}
+constexpr CaseInfo::CaseInfo(const Group group, const uint32_t case_id)
+    : group_(group), case_id_(case_id) {}
 
-constexpr uint32_t CaseInfo::case_id() const {
-    return case_id_;
+constexpr CaseInfo CaseInfo::unsafe_create(const Group group, const uint32_t case_id) {
+    return {group, case_id};
 }
 
 constexpr std::optional<CaseInfo> CaseInfo::create(const Group group, const uint32_t case_id) {
@@ -32,10 +48,6 @@ constexpr std::optional<CaseInfo> CaseInfo::create(const Group group, const uint
     return unsafe_create(group, case_id);
 }
 
-constexpr CaseInfo CaseInfo::unsafe_create(const Group group, const uint32_t case_id) {
-    return {group, case_id};
-}
-
-constexpr CaseInfo::CaseInfo(const Group group, const uint32_t case_id) : group_(group), case_id_(case_id) {}
+// ----------------------------------------------------------------------------------------- //
 
 } // namespace klotski::group

src/core/group/internal/constant/group.h

@@ -4,14 +4,21 @@
 
 namespace klotski::group {
 
-// seed(36) + size(20) + type(3)
-
+/// Properties of all patterns as follows:
+///   (H)  5-bit ~ Padding for u64.
+///       36-bit ~ The seed of the group with the Toward::A.
+///       20-bit ~ The number of cases in the included groups.
+///   (L)  3-bit ~ MirrorType enumeration of the included groups.
 constexpr auto PATTERN_DATA = std::to_array<uint64_t>({
 #include "pattern.inc"
 });
 
-// seed(36) + type_id(8) + pattern_id(10) + toward(2)
-
+/// Properties of all groups as follows:
+///   (H)  8-bit ~ Padding for u64.
+///       36-bit ~ The seed of current group.
+///        8-bit ~ The type_id of current group.
+///       10-bit ~ The pattern_id of current group.
+///   (L)  2-bit ~ Toward enumeration of current group.
 constexpr auto GROUP_DATA = std::to_array<uint64_t>({
 #include "group.inc"
 });

src/core/group/internal/constant/group_union.h

@@ -7,8 +7,6 @@
 namespace klotski::group {
 
 constexpr uint32_t TYPE_ID_LIMIT = 203;
-constexpr uint32_t ALL_GROUP_NUM = 25422; // TODO: from GROUP_NUM
-constexpr uint32_t ALL_PATTERN_NUM = 6577; // TODO: from PATTERN_NUM
 
 /// The number of groups contained in GroupUnion.
 constexpr auto GROUP_NUM = std::to_array<uint16_t>({
@@ -27,8 +25,11 @@ constexpr auto GROUP_NUM = std::to_array<uint16_t>({
     214, 6  , 18  , 54 , 2   , 44 , 40 , 124 , 84 , 70  , 18  ,
 });
 
+constexpr uint32_t ALL_GROUP_NUM = array_sum(GROUP_NUM);
+
 constexpr auto GROUP_OFFSET = to_offset<uint16_t, 203>(GROUP_NUM);
 
+/// The number of patterns contained in GroupUnion.
 constexpr auto PATTERN_NUM = std::to_array<uint16_t>({
     1 , 1  , 1  , 1  , 1  , 1  , 1 , 1  , 1  , 1  , 1  , 1  , 1 , 1  , 1  , 1  ,
     1 , 1  , 1  , 1  , 1  , 1  , 1 , 1  , 1  , 1  , 1  , 4  , 1 , 1  , 1  , 1  ,
@@ -45,7 +46,9 @@ constexpr auto PATTERN_NUM = std::to_array<uint16_t>({
     58, 2  , 6  , 15 , 1  , 11 , 12, 31 , 24 , 19 , 6  ,
 });
 
-const auto PATTERN_OFFSET = to_offset<uint16_t, 203>(PATTERN_NUM);
+constexpr uint32_t ALL_PATTERN_NUM = array_sum(PATTERN_NUM);
+
+constexpr auto PATTERN_OFFSET = to_offset<uint16_t, 203>(PATTERN_NUM);
 
 /// The maximum Group size in each GroupUnion.
 constexpr auto MAX_GROUP_SIZE = std::to_array<uint32_t>({
@@ -119,7 +122,7 @@ constexpr auto BLOCK_NUM = std::to_array<std::tuple<uint8_t, uint8_t, uint8_t>>(
     {7, 4, 0 }, {7, 5, 0 }, {7, 6, 0 },
 });
 
-/// The number of cases with different heads in GroupUnion.
+/// The number of cases with different heads in GroupUnion. (0/2/12/14, 1/13, 4/6/8/10, 5/9)
 constexpr auto GROUP_UNION_CASES_NUM = std::to_array<std::tuple<uint32_t, uint32_t, uint32_t, uint32_t>>({
     {1    , 1    , 1    , 1    }, {16   , 16   , 16   , 16   }, {120  , 120  , 120  , 120  },
     {560  , 560  , 560  , 560  }, {1820 , 1820 , 1820 , 1820 }, {4368 , 4368 , 4368 , 4368 },

src/core/group/internal/group.inl

@@ -2,12 +2,23 @@
 
 #include <format>
 
-#include "constant/group.h"
+#include "short_code/short_code.h"
+#include "common_code/common_code.h"
 
 namespace klotski::group {
 
 // ----------------------------------------------------------------------------------------- //
 
+constexpr uint32_t Group::flat_id() const {
+    return PATTERN_OFFSET[type_id_] + pattern_id_;
+}
+
+constexpr uint32_t Group::size() const {
+    return (PATTERN_DATA[flat_id()] >> 3) & 0xFFFFF;
+}
+
+// ----------------------------------------------------------------------------------------- //
+
 constexpr auto Group::toward() const -> Toward {
     return toward_;
 }
@@ -24,11 +35,11 @@ constexpr char Group::toward_char() const {
     // TODO: select chars from pre-build std::array
     switch (mirror_type()) {
         case MirrorType::Full:
-            return '\0';
+            return 'x';
         case MirrorType::Horizontal:
             return (toward_ == Toward::A) ? 'n' : 'u';
         case MirrorType::Centro:
-            return (toward_ == Toward::A) ? 'h' : 's';
+            return (toward_ == Toward::A) ? 's' : 'o';
         case MirrorType::Vertical:
             return (toward_ == Toward::A) ? 'p' : 'q';
         case MirrorType::Ordinary:
@@ -50,6 +61,16 @@ constexpr char Group::toward_char() const {
 
 // ----------------------------------------------------------------------------------------- //
 
+inline Group Group::from_short_code(const codec::ShortCode short_code) {
+    return from_common_code(short_code.to_common_code());
+}
+
+inline Group Group::from_common_code(const codec::CommonCode common_code) {
+    return from_raw_code(common_code.to_raw_code());
+}
+
+// ----------------------------------------------------------------------------------------- //
+
 #ifndef KLSK_NDEBUG
 inline std::ostream& operator<<(std::ostream &out, const Group self) {
     out << self.to_string();
@@ -57,12 +78,8 @@ inline std::ostream& operator<<(std::ostream &out, const Group self) {
 }
 #endif
 
-inline std::string Group::to_string() const {
-    auto c = toward_char();
-    if (c == '\0') {
-        return std::format("{}-{}", type_id_, pattern_id_);
-    }
-    return std::format("{}-{}{}", type_id_, pattern_id_, c);
+KLSK_INLINE_H std::string Group::to_string() const {
+    return std::format("{}-{}{}", type_id_, pattern_id_, toward_char());
 }
 
 constexpr auto operator==(const Group &lhs, const Group &rhs) {
@@ -71,18 +88,27 @@ constexpr auto operator==(const Group &lhs, const Group &rhs) {
         && lhs.pattern_id_ == rhs.pattern_id_;
 }
 
-constexpr Group Group::unsafe_create(const uint_fast8_t type_id, const uint_least16_t pattern_id, const Toward toward) {
+// ----------------------------------------------------------------------------------------- //
+
+constexpr Group::Group(const Toward toward,
+                       const uint_fast8_t type_id,
+                       const uint_least16_t pattern_id)
+    : toward_(toward), type_id_(type_id), pattern_id_(pattern_id) {}
+
+constexpr Group Group::unsafe_create(const uint_fast8_t type_id,
+                                     const uint_least16_t pattern_id,
+                                     const Toward toward) {
     return {toward, type_id, pattern_id};
 }
 
-constexpr std::optional<Group> Group::create(const uint_fast8_t type_id, const uint_least16_t pattern_id, const Toward toward) {
-    if (type_id >= TYPE_ID_LIMIT) {
-        return std::nullopt;
-    }
-    if (pattern_id >= GroupUnion::unsafe_create(type_id).pattern_num()) {
+constexpr std::optional<Group> Group::create(const uint_fast8_t type_id,
+                                             const uint_least16_t pattern_id,
+                                             const Toward toward) {
+    if (type_id >= TYPE_ID_LIMIT || pattern_id >= PATTERN_NUM[type_id]) {
         return std::nullopt;
     }
 
+    // TODO: perf check process
     if (toward == Toward::A) {
         return unsafe_create(type_id, pattern_id, toward);
     }
@@ -122,22 +148,6 @@ constexpr std::optional<Group> Group::create(const uint_fast8_t type_id, const u
     return std::nullopt; // TODO: never reach
 }
 
-constexpr uint32_t Group::flat_id() const {
-    return PATTERN_OFFSET[type_id_] + pattern_id_;
-}
-
-constexpr uint32_t Group::size() const {
-    return (PATTERN_DATA[flat_id()] >> 3) & 0xFFFFF;
-}
-
-inline Group Group::from_short_code(const codec::ShortCode short_code) {
-    return from_common_code(short_code.to_common_code());
-}
-
-inline Group Group::from_common_code(const codec::CommonCode common_code) {
-    return from_raw_code(common_code.to_raw_code());
-}
-
-constexpr Group::Group(const Toward toward, const uint_fast8_t type_id, const uint_least16_t pattern_id) : toward_(toward), type_id_(type_id), pattern_id_(pattern_id) {}
+// ----------------------------------------------------------------------------------------- //
 
 } // namespace klotski::group

src/core/group/internal/group_cases.inl

@@ -2,18 +2,20 @@
 
 namespace klotski::group {
 
-inline codec::CommonCode GroupCases::obtain_code(CaseInfo info) {
+// TODO: maybe move `fast_obtain_*` into `.inl` file
+
+inline codec::CommonCode GroupCases::obtain_code(const CaseInfo info) {
     if (fast_) {
         return fast_obtain_code(info);
     }
     return tiny_obtain_code(info);
 }
 
-inline CaseInfo GroupCases::obtain_info(const codec::CommonCode common_code) {
+inline Group GroupCases::obtain_group(const codec::ShortCode short_code) {
     if (fast_) {
-        return fast_obtain_info(common_code);
+        return fast_obtain_group(short_code);
     }
-    return tiny_obtain_info(common_code);
+    return Group::from_short_code(short_code);
 }
 
 inline Group GroupCases::obtain_group(const codec::CommonCode common_code) {
@@ -23,18 +25,18 @@ inline Group GroupCases::obtain_group(const codec::CommonCode common_code) {
     return Group::from_common_code(common_code);
 }
 
-inline Group GroupCases::obtain_group(const codec::ShortCode short_code) {
+inline CaseInfo GroupCases::obtain_info(const codec::ShortCode short_code) {
     if (fast_) {
-        return fast_obtain_group(short_code);
+        return fast_obtain_info(short_code);
     }
-    return Group::from_short_code(short_code);
+    return tiny_obtain_info(short_code.to_common_code());
 }
 
-inline CaseInfo GroupCases::obtain_info(const codec::ShortCode short_code) {
+inline CaseInfo GroupCases::obtain_info(const codec::CommonCode common_code) {
     if (fast_) {
-        return fast_obtain_info(short_code);
+        return fast_obtain_info(common_code);
     }
-    return tiny_obtain_info(short_code.to_common_code());
+    return tiny_obtain_info(common_code);
 }
 
 } // namespace klotski::group

src/core/group/internal/group_union.cc

@@ -1,5 +1,4 @@
 #include "group/group.h"
-#include "constant/group_union.h"
 
 using klotski::cases::Ranges;
 using klotski::group::GroupUnion;
@@ -8,21 +7,21 @@ using klotski::cases::RangesUnion;
 using klotski::cases::BASIC_RANGES_NUM;
 
 #define RANGE_DERIVE(HEAD) ranges.derive(HEAD, cases.ranges(HEAD))
+#define RANGE_RESERVE(HEAD, SIZE) cases.ranges(HEAD).reserve(SIZE)
 
 RangesUnion GroupUnion::cases() const {
-    auto [n, n_2x1, n_1x1] = BLOCK_NUM[type_id_];
-    auto [s_a, s_b, s_c, s_d] = GROUP_UNION_CASES_NUM[type_id_];
-
     Ranges ranges {};
     ranges.reserve(BASIC_RANGES_NUM[type_id_]);
+    const auto [n, n_2x1, n_1x1] = BLOCK_NUM[type_id_];
     ranges.spawn(n, n_2x1, n_1x1);
     ranges.reverse();
 
     RangesUnion cases;
-    cases.ranges(0x0).reserve(s_a); cases.ranges(0x1).reserve(s_b); cases.ranges(0x2).reserve(s_a);
-    cases.ranges(0x4).reserve(s_c); cases.ranges(0x5).reserve(s_d); cases.ranges(0x6).reserve(s_c);
-    cases.ranges(0x8).reserve(s_c); cases.ranges(0x9).reserve(s_d); cases.ranges(0xA).reserve(s_c);
-    cases.ranges(0xC).reserve(s_a); cases.ranges(0xD).reserve(s_b); cases.ranges(0xE).reserve(s_a);
+    const auto [s_a, s_b, s_c, s_d] = GROUP_UNION_CASES_NUM[type_id_];
+    RANGE_RESERVE(0x0, s_a); RANGE_RESERVE(0x1, s_b); RANGE_RESERVE(0x2, s_a);
+    RANGE_RESERVE(0x4, s_c); RANGE_RESERVE(0x5, s_d); RANGE_RESERVE(0x6, s_c);
+    RANGE_RESERVE(0x8, s_c); RANGE_RESERVE(0x9, s_d); RANGE_RESERVE(0xA, s_c);
+    RANGE_RESERVE(0xC, s_a); RANGE_RESERVE(0xD, s_b); RANGE_RESERVE(0xE, s_a);
 
     RANGE_DERIVE(0x0); RANGE_DERIVE(0x1); RANGE_DERIVE(0x2);
     RANGE_DERIVE(0x4); RANGE_DERIVE(0x5); RANGE_DERIVE(0x6);

src/core/group/internal/group_union.inl

@@ -1,7 +1,10 @@
 #pragma once
 
 #include <ranges>
-#include <ostream> // TODO: only for debug output
+
+#include "raw_code/raw_code.h"
+#include "short_code/short_code.h"
+#include "common_code/common_code.h"
 
 namespace klotski::group {
 
@@ -44,7 +47,7 @@ constexpr std::optional<GroupUnion> GroupUnion::create(const uint_fast8_t type_i
 
 #ifndef KLSK_NDEBUG
 inline std::ostream& operator<<(std::ostream &out, GroupUnion self) {
-    out << static_cast<int>(self.type_id_);
+    out << std::format("{}", self.type_id_);
     return out;
 }
 #endif
@@ -69,8 +72,9 @@ constexpr GroupUnion GroupUnion::from_common_code(const codec::CommonCode common
 
 // ----------------------------------------------------------------------------------------- //
 
-constexpr auto GroupUnion::groups() const -> Groups {
-    auto build = [this](size_t offset) {
+// TODO: benchmark of force-inline
+inline auto GroupUnion::groups() const -> Groups {
+    auto build = [this](const size_t offset) {
         const auto raw = GROUP_DATA[offset];
         const uint_fast16_t pattern_id = (raw >> 2) & 0x3FF;
         const auto toward = static_cast<Group::Toward>(raw & 0b11);
@@ -82,12 +86,13 @@ constexpr auto GroupUnion::groups() const -> Groups {
          | std::ranges::to<std::vector>();
 }
 
-constexpr auto GroupUnion::groups(const uint_least16_t pattern_id) const -> std::optional<Groups> {
+// TODO: benchmark of force-inline
+inline auto GroupUnion::groups(const uint_least16_t pattern_id) const -> std::optional<Groups> {
     if (pattern_id >= pattern_num()) {
         return std::nullopt;
     }
 
-    auto flat_id = PATTERN_OFFSET[type_id_] + pattern_id;
+    const auto flat_id = PATTERN_OFFSET[type_id_] + pattern_id;
     switch (static_cast<Group::MirrorType>(PATTERN_DATA[flat_id] & 0b111)) {
         case Group::MirrorType::Full:
             return Groups {

src/core/group/internal/hash.inl

@@ -1,30 +0,0 @@
-#pragma once
-
-namespace std {
-
-template <>
-struct hash<klotski::group::Group> {
-    constexpr std::size_t operator()(const klotski::group::Group &g) const noexcept {
-        // TODO: perf hash alg
-        return std::hash<uint64_t>{}(g.type_id() ^ g.pattern_id() ^ (int)g.toward());
-    }
-};
-
-template <>
-struct hash<klotski::group::GroupUnion> {
-    constexpr std::size_t operator()(const klotski::group::GroupUnion &gu) const noexcept {
-        return std::hash<uint32_t>{}(gu.unwrap());
-    }
-};
-
-template <>
-struct hash<klotski::group::CaseInfo> {
-    constexpr std::size_t operator()(const klotski::group::CaseInfo &info) const noexcept {
-        // TODO: perf hash alg
-        const auto h1 = std::hash<klotski::group::Group>{}(info.group());
-        const auto h2 = std::hash<uint32_t>{}(info.case_id());
-        return h1 ^ h2;
-    }
-};
-
-} // namespace std

src/core/group/internal/type_id.inl

@@ -1,5 +1,7 @@
 #pragma once
 
+#include "common_code/common_code.h"
+
 namespace klotski::group {
 
 KLSK_INLINE_CE uint_fast8_t to_type_id(const int n, const int n_2x1, const int n_1x1) {

src/core_test/group/group_union.cc

@@ -22,6 +22,22 @@ using klotski::group::GroupUnion;
 using klotski::group::TYPE_ID_LIMIT;
 using klotski::group::ALL_GROUP_NUM;
 
+static_assert(std::is_standard_layout_v<GroupUnion>);
+static_assert(std::is_trivially_copyable_v<GroupUnion>);
+static_assert(!std::is_default_constructible_v<GroupUnion>);
+static_assert(std::is_trivially_destructible_v<GroupUnion>);
+static_assert(std::is_nothrow_destructible_v<GroupUnion>);
+
+static_assert(std::is_nothrow_copy_assignable_v<GroupUnion>);
+static_assert(std::is_nothrow_move_assignable_v<GroupUnion>);
+static_assert(std::is_nothrow_copy_constructible_v<GroupUnion>);
+static_assert(std::is_nothrow_move_constructible_v<GroupUnion>);
+
+static_assert(std::is_trivially_copy_assignable_v<GroupUnion>);
+static_assert(std::is_trivially_move_assignable_v<GroupUnion>);
+static_assert(std::is_trivially_copy_constructible_v<GroupUnion>);
+static_assert(std::is_trivially_move_constructible_v<GroupUnion>);
+
 #define EXPECT_REPEAT(R, val)  \
     EXPECT_FALSE(R.empty());   \
     EXPECT_EQ(R.front(), val); \