🎨 更改为libmemdb

libmemdb/.gitignore

@@ -0,0 +1,69 @@
+# Prerequisites
+*.d
+
+# Compiled Object files
+*.slo
+*.lo
+*.o
+*.obj
+
+# Precompiled Headers
+*.gch
+*.pch
+
+# Linker files
+*.ilk
+
+# Debugger Files
+*.pdb
+
+# Compiled Dynamic libraries
+*.so
+*.dylib
+*.dll
+*.so.*
+
+
+# Fortran module files
+*.mod
+*.smod
+
+# Compiled Static libraries
+*.lai
+*.la
+*.a
+*.lib
+
+# Executables
+*.exe
+*.out
+*.app
+
+# Build directories
+build/
+Build/
+build-*/
+
+# CMake generated files
+CMakeFiles/
+CMakeCache.txt
+cmake_install.cmake
+#Makefile
+install_manifest.txt
+compile_commands.json
+
+# Temporary files
+*.tmp
+*.log
+*.bak
+*.swp
+
+# vcpkg
+vcpkg_installed/
+
+# debug information files
+*.dwo
+
+# test output & cache
+Testing/
+.cache/

libmemdb/Makefile

@@ -0,0 +1,25 @@
+VERSION := 1.0.0
+FRAMEWORK_NAME := us
+LIB_NAME := libus_memdb
+INSTL_TDIR := /lib
+INCLU_TDIR := /usr/include
+INCLU_SDIR := inc
+CPP := g++
+INCS := -I inc
+CPPFLAGS := --std=c++20 -O3 -pipe -Wall -Werror
+LIBS :=
+BUILD_TDIR := build
+$(shell mkdir -p $(BUILD_TDIR))
+
+
+
+install:
+	@echo "install UniServe_libmemdb..."
+	@mkdir -vp $(INCLU_TDIR)/${FRAMEWORK_NAME}
+	@cp -vf $(INCLU_SDIR)/$(FRAMEWORK_NAME)/memdb.hpp $(INCLU_TDIR)/$(FRAMEWORK_NAME)/
+	@echo "done."
+
+uninstall:
+	@echo "uninstall UniServe_libmemdb..."
+	@rm -vf $(INCLU_TDIR)/$(FRAMEWORK_NAME)/memdb.hpp
+	@echo "done."

libmemdb/README.md

@@ -0,0 +1,5 @@
+# UniServe_libmemdb
+UniServe Framework memdb Library
+
+# Dependancy
+libmemdb-dev

libmemdb/_set.sh

@@ -0,0 +1,3 @@
+#!/bin/bash
+cd "$(dirname "$0")" || exit
+make install

libmemdb/inc/us/memdb.hpp

@@ -0,0 +1,156 @@
+#pragma once
+#include <list>
+#include <unordered_map>
+#include <chrono>
+#include <set>
+#include <optional>
+#include <cmath>
+
+
+
+namespace shufeng2012 {
+
+
+
+template <typename T, typename U>
+
+class Memdb {
+
+
+struct memdb_column {
+    T key;
+    U value;
+    std::chrono::system_clock::time_point timestamp;
+};
+
+struct index_keys {
+    T key;
+    std::list <memdb_column>::iterator item;
+};
+
+struct index_timestamp {
+    std::list <memdb_column>::iterator item;
+
+    bool operator<(const index_timestamp& a) const {
+        return this -> item -> timestamp < a.item -> timestamp;
+    }
+};
+
+
+private:
+    std::list <memdb_column> db;
+    std::unordered_map <T, index_keys> keys;
+    std::multiset <index_timestamp> time_touch;
+    size_t __size = 0;
+    int MAX_TIME = 60 * 10;       // 10分钟
+    void flush();
+
+
+
+public:
+    using key_t = T;
+    using value_t = U;
+    static constexpr bool fail = false;
+    static constexpr bool succ = true;
+
+
+
+    Memdb() = default;
+    Memdb(int max_time) : MAX_TIME(std::max(0, max_time)) {}
+    Memdb& operator=(const Memdb& to_be_cp_memdb) = default;
+    ~Memdb() = default;
+
+
+    size_t size() const {
+        return this -> __size;
+    }
+
+    const std::unordered_map <T, index_keys>& get_keys() const {
+        return this -> keys;
+    }
+
+    const std::list <memdb_column>& get_db() const {
+        return this -> db;
+    }
+
+    const std::multiset <typename Memdb <T, U>::index_timestamp>& get_time_touch() const {
+        return this -> time_touch;
+    }
+
+
+    bool insert(key_t to_be_ins_k, value_t ins_v) {
+        this -> flush();
+        if (this -> keys.find(to_be_ins_k) != this -> keys.end()) {
+            return this -> fail;
+        }
+
+        std::chrono::system_clock::time_point now_time = std::chrono::system_clock::now();
+
+        Memdb::memdb_column new_column;
+        new_column.key = to_be_ins_k;
+        new_column.value = ins_v;
+        new_column.timestamp = now_time + std::chrono::seconds(MAX_TIME);
+        this -> db.push_back(new_column);
+
+        Memdb::index_keys new_key;
+        new_key.key = to_be_ins_k;
+        new_key.item = std::prev(this -> db.end());
+        this -> keys[to_be_ins_k] = new_key;
+
+        Memdb::index_timestamp new_time_touch;
+        new_time_touch.item = std::prev(this -> db.end());
+        this -> time_touch.insert(new_time_touch);
+
+        this -> __size++;
+
+        return this -> succ;
+    }
+
+    bool remove(key_t to_be_del_k) {
+        this -> flush();
+        if (this -> keys.find(to_be_del_k) == this -> keys.end()) {
+            return this -> fail;
+        }
+
+        typename std::list <memdb_column>::iterator it = this -> keys[to_be_del_k].item;
+        this -> keys.erase(it -> key);
+        this -> time_touch.erase({it});
+        this -> db.erase(it);
+        this -> __size--;
+
+        return this -> succ;
+    }
+
+    bool update(key_t to_be_udt_k, value_t udt_v, bool need_to_udt_timetouch=false) {
+        this -> flush();
+        if (this -> keys.find(to_be_udt_k) == this -> keys.end()) {
+            return this -> fail;
+        }
+
+        typename std::list <memdb_column>::iterator it = this -> keys[to_be_udt_k].item;
+        it -> value = udt_v;
+        if (need_to_udt_timetouch == true) {
+            std::chrono::system_clock::time_point now_time = std::chrono::system_clock::now();
+            T copy_k = it -> key;
+            U copy_v = it -> value;
+            this -> remove(copy_k);
+            this -> insert(copy_k, copy_v);
+        }
+
+        return this -> succ;
+    }
+
+    std::optional<U> search(key_t to_be_sch_k) {
+        this -> flush();
+        if (this -> keys.find(to_be_sch_k) == this -> keys.end()) {
+            return std::nullopt;
+        }
+
+        typename std::list <memdb_column>::iterator it = this -> keys[to_be_sch_k].item;
+        return it -> value;
+    }
+};
+
+
+
+}

memdb/.gitignore

@@ -1,3 +0,0 @@
-*.bin
-*.obj
-build/

memdb/Makefile

@@ -1,2 +0,0 @@
-test: src/blackbox_test.cpp src/main/memdb.cpp include/memdb.hpp
-	g++ src/blackbox_test.cpp -o test.bin -I include/ -std=c++20 -O3 -g

memdb/include/memdb.hpp

@@ -1,66 +0,0 @@
-#pragma once
-#include <list>
-#include <unordered_map>
-#include <chrono>
-#include <set>
-#include <optional>
-#include <cmath>
-
-
-
-namespace shufeng2012 {
-
-template <typename T, typename U>
-
-class Memdb {
-
-
-struct memdb_column {
-    T key;
-    U value;
-    std::chrono::system_clock::time_point timestamp;
-};
-
-struct index_keys {
-    T key;
-    std::list <memdb_column>::iterator item;
-};
-
-struct index_timestamp {
-    std::list <memdb_column>::iterator item;
-
-    bool operator<(const index_timestamp& a) const;
-};
-
-
-private:
-    std::list <memdb_column> db;
-    std::unordered_map <T, index_keys> keys;
-    std::multiset <index_timestamp> time_touch;
-    size_t __size = 0;
-    int MAX_TIME = 60 * 10;       // 10分钟
-    void flush();
-
-
-public:
-    using key_t = T;
-    using value_t = U;
-    static constexpr bool fail = false;
-    static constexpr bool succ = true;
-
-    Memdb();
-    Memdb(int max_time);
-    Memdb& operator=(const Memdb& to_be_cp_memdb);
-    ~Memdb();
-
-    size_t size() const;
-    const std::unordered_map <T, index_keys>& get_keys() const;
-    const std::list <memdb_column>& get_db() const;
-    const std::multiset <typename Memdb <T, U>::index_timestamp>& get_time_touch() const;
-
-    bool insert(key_t to_be_ins_k, value_t ins_v);
-    bool remove(key_t to_be_del_k);
-    bool update(key_t to_be_udt_k, value_t udt_v, bool need_to_udt_timetouch=false);
-    std::optional<U> search(key_t to_be_sch_k);
-};
-}

memdb/src/blackbox_test.cpp

@@ -1,291 +0,0 @@
-#include <iostream>
-#include <chrono>
-#include <thread>
-#include <string>
-#include <optional>
-#include <functional>
-#include <vector>
-#include <utility>
-
-// 使用 C++20 的时间字面量
-using namespace std::chrono_literals;
-using namespace shufeng2012;
-
-#include "main/memdb.cpp"
-
-// ----- 简易测试框架 -----
-static int g_test_passed = 0;
-static int g_test_failed = 0;
-
-#define TEST(name) \
-    void test_##name(); \
-    struct TestReg_##name { \
-        TestReg_##name() { register_test(#name, test_##name); } \
-    } reg_##name; \
-    void test_##name()
-
-using TestFunc = std::function<void()>;
-std::vector<std::pair<std::string, TestFunc>> tests;
-
-void register_test(const std::string& name, TestFunc fn) {
-    tests.push_back({name, fn});
-}
-
-// 断言宏（支持 C++20 的 constexpr 字符串，但这里不变）
-#define EXPECT_TRUE(expr) \
-    do { if (!(expr)) { std::cerr << "  [FAIL] " #expr << " is false\n"; ++g_test_failed; return; } } while(0)
-
-#define EXPECT_FALSE(expr) EXPECT_TRUE(!(expr))
-
-#define EXPECT_EQ(expected, actual) \
-    do { if ((expected) != (actual)) { std::cerr << "  [FAIL] Expected: " << (expected) << ", Actual: " << (actual) << "\n"; ++g_test_failed; return; } } while(0)
-
-#define EXPECT_OPTIONAL_EQ(expected, opt) \
-    do { \
-        if (!(opt).has_value()) { std::cerr << "  [FAIL] optional has no value\n"; ++g_test_failed; return; } \
-        if ((expected) != (opt).value()) { std::cerr << "  [FAIL] Expected: " << (expected) << ", Actual: " << (opt).value() << "\n"; ++g_test_failed; return; } \
-    } while(0)
-
-#define EXPECT_NO_VALUE(opt) \
-    do { if ((opt).has_value()) { std::cerr << "  [FAIL] optional should have no value, but has: " << (opt).value() << "\n"; ++g_test_failed; return; } } while(0)
-
-// ----- 测试用例 -----
-
-// 1. 默认构造
-TEST(DefaultConstruction) {
-    Memdb<int, std::string> db;
-    EXPECT_EQ(0u, db.size());
-    EXPECT_TRUE(db.get_db().empty());
-    EXPECT_TRUE(db.get_keys().empty());
-    EXPECT_TRUE(db.get_time_touch().empty());
-    std::cout << "  [PASS]\n";
-    ++g_test_passed;
-}
-
-// 2. 插入与查询
-TEST(InsertAndSearch) {
-    Memdb<int, std::string> db(10);
-    EXPECT_TRUE(db.insert(1, "one"));
-    EXPECT_EQ(1u, db.size());
-    auto opt = db.search(1);
-    EXPECT_OPTIONAL_EQ("one", opt);
-    std::cout << "  [PASS]\n";
-    ++g_test_passed;
-}
-
-// 3. 重复插入失败
-TEST(InsertDuplicateFails) {
-    Memdb<int, std::string> db;
-    EXPECT_TRUE(db.insert(1, "one"));
-    EXPECT_FALSE(db.insert(1, "another"));
-    EXPECT_EQ(1u, db.size());
-    auto opt = db.search(1);
-    EXPECT_OPTIONAL_EQ("one", opt);
-    std::cout << "  [PASS]\n";
-    ++g_test_passed;
-}
-
-// 4. 查询不存在的键
-TEST(SearchNonExistent) {
-    Memdb<int, std::string> db;
-    auto opt = db.search(42);
-    EXPECT_NO_VALUE(opt);
-    std::cout << "  [PASS]\n";
-    ++g_test_passed;
-}
-
-// 5. 删除存在的键
-TEST(RemoveExisting) {
-    Memdb<int, std::string> db;
-    db.insert(1, "one");
-    EXPECT_TRUE(db.remove(1));
-    EXPECT_EQ(0u, db.size());
-    auto opt = db.search(1);
-    EXPECT_NO_VALUE(opt);
-    std::cout << "  [PASS]\n";
-    ++g_test_passed;
-}
-
-// 6. 删除不存在的键
-TEST(RemoveNonExistentFails) {
-    Memdb<int, std::string> db;
-    EXPECT_FALSE(db.remove(99));
-    EXPECT_EQ(0u, db.size());
-    std::cout << "  [PASS]\n";
-    ++g_test_passed;
-}
-
-// 7. 删除后重新插入
-TEST(RemoveThenReinsert) {
-    Memdb<int, std::string> db;
-    db.insert(1, "one");
-    db.remove(1);
-    EXPECT_TRUE(db.insert(1, "new"));
-    EXPECT_EQ(1u, db.size());
-    auto opt = db.search(1);
-    EXPECT_OPTIONAL_EQ("new", opt);
-    std::cout << "  [PASS]\n";
-    ++g_test_passed;
-}
-
-// 8. 更新（不触摸）
-TEST(UpdateWithoutTouch) {
-    Memdb<int, std::string> db(10);
-    db.insert(1, "one");
-    EXPECT_TRUE(db.update(1, "updated", false));
-    EXPECT_EQ(1u, db.size());
-    auto opt = db.search(1);
-    EXPECT_OPTIONAL_EQ("updated", opt);
-    std::cout << "  [PASS]\n";
-    ++g_test_passed;
-}
-
-// 9. 更新（触摸）延长寿命 —— 使用 C++20 字面量
-TEST(UpdateWithTouchExtendsLifetime) {
-    const int TTL = 3;
-    Memdb<int, std::string> db(TTL);
-    db.insert(1, "one");
-
-    // 等待 1.5 秒（剩余寿命约 1.5 秒）
-    std::this_thread::sleep_for(1500ms);
-
-    // 触摸更新，重置寿命为从当前起 TTL 秒
-    EXPECT_TRUE(db.update(1, "touched", true));
-
-    // 再等待 2.5 秒（从触摸起 2.5 < TTL，应存活）
-    std::this_thread::sleep_for(2500ms);
-
-    db.search(999);   // 触发 flush
-    auto opt = db.search(1);
-    EXPECT_TRUE(opt.has_value());
-    EXPECT_OPTIONAL_EQ("touched", opt);
-    EXPECT_EQ(1u, db.size());
-
-    std::cout << "  [PASS]\n";
-    ++g_test_passed;
-}
-
-// 10. 更新不存在的键
-TEST(UpdateNonExistentFails) {
-    Memdb<int, std::string> db;
-    EXPECT_FALSE(db.update(2, "nope"));
-    EXPECT_EQ(0u, db.size());
-    std::cout << "  [PASS]\n";
-    ++g_test_passed;
-}
-
-// 11. 过期后自动清除
-TEST(ExpirationAfterTimeout) {
-    const int TTL = 2;
-    Memdb<int, std::string> db(TTL);
-    db.insert(1, "expire");
-
-    // 等待 TTL + 1 秒（保证超过）
-    std::this_thread::sleep_for(std::chrono::seconds(TTL + 1));
-
-    db.search(999);   // 触发 flush
-    EXPECT_EQ(0u, db.size());
-    EXPECT_NO_VALUE(db.search(1));
-
-    std::cout << "  [PASS]\n";
-    ++g_test_passed;
-}
-
-// 12. 未过期前可查询
-TEST(NotExpiredBeforeTimeout) {
-    const int TTL = 2;
-    Memdb<int, std::string> db(TTL);
-    db.insert(1, "alive");
-    std::this_thread::sleep_for(1s);
-    EXPECT_EQ(1u, db.size());
-    auto opt = db.search(1);
-    EXPECT_OPTIONAL_EQ("alive", opt);
-    std::cout << "  [PASS]\n";
-    ++g_test_passed;
-}
-
-// 13. 更新不触摸不延长寿命
-TEST(UpdateWithoutTouchDoesNotExtend) {
-    const int TTL = 3;
-    Memdb<int, std::string> db(TTL);
-    db.insert(1, "one");
-
-    // 等待 1.5 秒（剩余 1.5 秒）
-    std::this_thread::sleep_for(1500ms);
-
-    // 更新但不触摸，过期时间不变
-    EXPECT_TRUE(db.update(1, "updated", false));
-
-    // 再等待 2 秒（总休眠 3.5 > TTL，应过期）
-    std::this_thread::sleep_for(2000ms);
-
-    db.search(999);
-    EXPECT_EQ(0u, db.size());
-    EXPECT_NO_VALUE(db.search(1));
-
-    std::cout << "  [PASS]\n";
-    ++g_test_passed;
-}
-
-// 14. 生存时间为 0，立即过期
-TEST(ZeroLifetimeExpiresImmediately) {
-    Memdb<int, std::string> db(0);
-    db.insert(1, "zero");
-    std::this_thread::sleep_for(10ms);
-    db.search(999);
-    EXPECT_EQ(0u, db.size());
-    EXPECT_NO_VALUE(db.search(1));
-    std::cout << "  [PASS]\n";
-    ++g_test_passed;
-}
-
-// 15. 混合操作一致性
-TEST(MixedInsertDeleteSize) {
-    Memdb<int, std::string> db;
-    db.insert(1, "a");
-    db.insert(2, "b");
-    db.insert(3, "c");
-    db.remove(2);
-    db.insert(4, "d");
-    EXPECT_EQ(3u, db.size());
-    EXPECT_TRUE(db.search(1).has_value());
-    EXPECT_FALSE(db.search(2).has_value());
-    EXPECT_TRUE(db.search(3).has_value());
-    EXPECT_TRUE(db.search(4).has_value());
-    std::cout << "  [PASS]\n";
-    ++g_test_passed;
-}
-
-// 16. 批量过期
-TEST(BulkExpirationClearsSize) {
-    const int TTL = 1;
-    Memdb<int, std::string> db(TTL);
-    for (int i = 0; i < 100; ++i) {
-        db.insert(i, std::to_string(i));
-    }
-    EXPECT_EQ(100u, db.size());
-    std::this_thread::sleep_for(std::chrono::seconds(TTL + 1));
-    db.search(-1);
-    EXPECT_EQ(0u, db.size());
-    for (int i = 0; i < 100; ++i) {
-        EXPECT_FALSE(db.search(i).has_value());
-    }
-    std::cout << "  [PASS]\n";
-    ++g_test_passed;
-}
-
-// ----- 程序入口 -----
-int main() {
-    std::cout << "Memdb Black-box Tests (C++20, no external libs)\n";
-    std::cout << "================================================\n";
-
-    for (auto& [name, fn] : tests) {
-        std::cout << "Test: " << name << "\n";
-        fn();
-    }
-
-    std::cout << "================================================\n";
-    std::cout << "Passed: " << g_test_passed << ", Failed: " << g_test_failed << "\n";
-
-    return g_test_failed > 0 ? 1 : 0;
-}

memdb/src/main.cpp

@@ -1,13 +0,0 @@
-#include <bits/stdc++.h>
-#include "main/memdb.cpp"
-using namespace std;
-Memdb<string,string> testdb(10);
-int main(){
-    testdb.insert_("key1","value1");
-    auto pack=testdb.search_("key1");
-    cout<<(pack==nullopt?"未找到":pack.value())<<endl;
-    this_thread::sleep_for(std::chrono::seconds(10));
-    auto pack2=testdb.search_("key1");
-    cout<<(pack2==nullopt?"未找到":pack2.value())<<endl;
-    return 0;
-}

memdb/src/main/memdb.cpp

@@ -1,177 +0,0 @@
-#include "memdb.hpp"
-
-
-
-namespace shufeng2012 {
-template <typename T, typename U>
-
-bool Memdb <T, U>::index_timestamp::operator<(const index_timestamp& a) const {
-    return this -> item -> timestamp < a.item -> timestamp;
-}
-
-
-template <typename T, typename U>
-
-Memdb <T, U>::Memdb() = default;
-
-
-template <typename T, typename U>
-
-Memdb <T, U>::Memdb(int max_time) : MAX_TIME(std::max(0, max_time)) {}
-
-
-template <typename T, typename U>
-
-Memdb <T, U>& Memdb <T, U>::operator=(const Memdb <T, U>& to_be_cp_memdb) = default;
-
-
-template <typename T, typename U>
-
-Memdb <T, U>::~Memdb() = default;
-
-
-template <typename T, typename U>
-
-size_t Memdb <T, U>::size() const {
-    return this -> __size;
-}
-
-
-template <typename T, typename U>
-
-const std::unordered_map <T, typename Memdb <T, U>::index_keys>& Memdb <T, U>::get_keys() const {
-    return this -> keys;
-}
-
-
-template <typename T, typename U>
-
-const std::list <typename Memdb <T, U>::memdb_column>& Memdb <T, U>::get_db() const {
-    return this -> db;
-}
-
-
-/*
-内测版
-*/
-
-
-template <typename T, typename U>
-
-void Memdb <T, U>::flush() {
-    if (this -> time_touch.empty() == true) {
-        return;
-    }
-    std::chrono::system_clock::time_point now_time = std::chrono::system_clock::now();
-    typename std::list <memdb_column>::iterator it = this -> time_touch.begin() -> item;
-
-    while (now_time >= it -> timestamp) {
-        this -> __size--;
-        key_t to_be_del_k = it -> key;
-        this -> db.erase(it);
-        this -> keys.erase(to_be_del_k);
-		this -> time_touch.erase(this -> time_touch.begin());
-
-        if (this -> time_touch.empty() == true) {
-            return;
-        }
-        it = this -> time_touch.begin() -> item;
-        now_time = std::chrono::system_clock::now();
-    }
-}
-
-
-template <typename T, typename U>
-
-const std::multiset <typename Memdb <T, U>::index_timestamp>& Memdb <T, U>::get_time_touch() const {
-    return this -> time_touch;
-}
-
-
-template <typename T, typename U>
-
-bool Memdb <T, U>::insert(key_t to_be_ins_k, value_t ins_v) {
-    this -> flush();
-    if (this -> keys.find(to_be_ins_k) != this -> keys.end()) {
-        return this -> fail;
-    }
-
-    std::chrono::system_clock::time_point now_time = std::chrono::system_clock::now();
-
-    Memdb::memdb_column new_column;
-    new_column.key = to_be_ins_k;
-    new_column.value = ins_v;
-    new_column.timestamp = now_time + std::chrono::seconds(MAX_TIME);
-    this -> db.push_back(new_column);
-
-    Memdb::index_keys new_key;
-    new_key.key = to_be_ins_k;
-    new_key.item = std::prev(this -> db.end());
-    this -> keys[to_be_ins_k] = new_key;
-
-    Memdb::index_timestamp new_time_touch;
-    new_time_touch.item = std::prev(this -> db.end());
-    this -> time_touch.insert(new_time_touch);
-
-    this -> __size++;
-
-    return this -> succ;
-}
-
-
-template <typename T, typename U>
-
-bool Memdb <T, U>::remove(key_t to_be_del_k) {
-    //! 直接删除，不要lazy
-    this -> flush();
-    if (this -> keys.find(to_be_del_k) == this -> keys.end()) {
-        return this -> fail;
-    }
-
-    typename std::list <memdb_column>::iterator it = this -> keys[to_be_del_k].item;
-    // it -> be_del = true;
-    this -> keys.erase(it -> key);
-    this -> time_touch.erase({it});
-    this -> db.erase(it);
-    this -> __size--;
-
-    return this -> succ;
-}
-
-
-template <typename T, typename U>
-
-bool Memdb <T, U>::update(key_t to_be_udt_k, value_t udt_v, bool need_to_udt_timetouch) {
-    //! 先删再加
-    this -> flush();
-    if (this -> keys.find(to_be_udt_k) == this -> keys.end()) {
-        return this -> fail;
-    }
-
-    typename std::list <memdb_column>::iterator it = this -> keys[to_be_udt_k].item;
-    it -> value = udt_v;
-    if (need_to_udt_timetouch == true) {
-        std::chrono::system_clock::time_point now_time = std::chrono::system_clock::now();
-        T copy_k = it -> key;
-        U copy_v = it -> value;
-        this -> remove(copy_k);
-        this -> insert(copy_k, copy_v);
-    }
-
-    return this -> succ;
-}
-
-
-template <typename T, typename U>
-
-std::optional<U> Memdb <T, U>::search(key_t to_be_sch_k){
-    this -> flush();
-    if (this -> keys.find(to_be_sch_k) == this -> keys.end()) {
-        return std::nullopt;
-    }
-
-    typename std::list <memdb_column>::iterator it = this -> keys[to_be_sch_k].item;
-    return it -> value;
-}
-
-}