removed a the redundantly explicit std::uniques

from display_wallet.h and display_wallet.cpp

They are now all wrapped in the long promised
and long forgotten wrapper class.

Long, long ago, I intended to implement the Pimpl idiom,
but these days std::unique takes care of all that work for
you.  You just wrap your low level pimple class in a high
level wrapper whose base class is an std_unique_ptr to
to an instance of your low level class.

msvc/wallet.vcxproj

@@ -150,6 +150,7 @@
   <ItemGroup>
     <ClCompile Include="../src/app.cpp" />
     <ClCompile Include="../src/display_wallet.cpp" />
+    <ClCompile Include="../src/db_accessors.cpp" />
     <ClCompile Include="../src/frame.cpp" />
     <ClCompile Include="../src/ILog.cpp" />
     <ClCompile Include="../src/ISqlit3Impl.cpp">

src/ISqlite3.h

@@ -1,13 +1,8 @@
 #pragma once
 #include "ILog.h"
-//	this is pure virtual interface base class between sqlite3, which speaks only C and utf8 char[]
+//	this is an interface base class between sqlite3, which speaks only C and utf8 char[]
 //	and wxWidgets which speaks only C++ and unicode strings.
 
-//	Usage:  Call the factory function std::shared_ptr<ISqlite3> sqlite3_open(const char *) to get a shared
-//	pointer to the //	Sqlite3 database object. Then call the factory function
-//	sqlite3_prepare(std::shared_ptr<ISqlite3>, const char *) to get a unique pointer to
-//	a compiled SQL statement
-
 //	Its primary purpose is to avoid code that needs both the wxWidgets header files,
 //	and the sqlite3.h header file.
 //
@@ -25,8 +20,6 @@
 //	substantially more difficult in C++14, because one is effectively rolling one's own
 //	unique pointer.
 //
-//	It is therefore easier to implement a pure virtual base class with a virtual destructor and
-//	factory function that returns a smart pointer to a member of the derived implementation
 //
 /*	This code is at a low level abstraction, because it provides low level C++ interface to inherently low level C
 	It is intended to be wrapped in higher level code that does not know about the nuts and bolts of sqlite3, but which supports throwing, templated functions, and all that.*/

src/db_accessors.cpp

@@ -0,0 +1,45 @@
+#include "stdafx.h"
+namespace ro {
+	static constexpr char SrcFilename[]{ "src/db_accessors.cpp" };
+
+	dbconnect::dbconnect(const wxFileName& filename) {
+		if (!filename.IsOk() || !filename.HasName() || !filename.HasExt()) throw
+			MyException("unexpected file name", __LINE__, __func__, SrcFilename);
+		if (!filename.FileExists())throw MyException(
+			std::string(filename.GetFullPath().ToUTF8()) + " does not exist.",
+			__LINE__, __func__, SrcFilename);
+		this->reset(Sqlite3_open(filename.GetFullPath().ToUTF8()));
+	}
+
+	//	move constructor
+	dbconnect::dbconnect(dbconnect&& p) noexcept :std::unique_ptr<ISqlite3>(p.release()) {
+	}
+
+	//	Move assignment
+	dbconnect& dbconnect::operator=(dbconnect&& p) noexcept {
+		std::unique_ptr<ISqlite3>::reset(p.release());
+		return *this;
+	}
+
+	sql::sql(const std::unique_ptr<ISqlite3>& p, const char* sz) :
+		std::unique_ptr<Icompiled_sql>(sqlite3_prepare(p.get(), sz)) {
+	}
+
+	//	move constructor
+	sql::sql(sql&& p) noexcept :std::unique_ptr<Icompiled_sql>(p.release()) {
+	}
+
+	//	Move assignment
+	sql& sql::operator=(sql&& p) noexcept {
+		std::unique_ptr<Icompiled_sql>::reset(p.release());
+		return *this;
+	}
+
+	sql::sql(Icompiled_sql* p) :
+		std::unique_ptr<Icompiled_sql>(p) {
+	}
+
+	sql::sql(std::unique_ptr<Icompiled_sql>&& p) :
+		std::unique_ptr<Icompiled_sql>(p.release()) {
+	}
+}

src/db_accessors.h

@@ -15,26 +15,43 @@ namespace ro {
 
 	static_assert(is_sqlite3_field_type<int>::value);
 
+	//Owns a database connection and closes it when it is deconstructed
+	//Has move semantics
+	class dbconnect : public std::unique_ptr<ISqlite3> {
+	public:
+		dbconnect(const wxFileName&);  //And here we wrap our Cish implementation in C++ish implementation
+		dbconnect() = delete;
+		~dbconnect() = default;  //Our base class takes care of it
+		//	copy constructor
+		dbconnect(const dbconnect& a) = delete;   //Move semantics
+		//	move constructor
+		dbconnect(dbconnect&& p) noexcept;
+		//	copy assignment
+		dbconnect& operator=(const dbconnect) = delete; //Move semantics
+		//	Move assignment
+		dbconnect& operator=(dbconnect&& p) noexcept;
+	};
+
 	//Owns a compiled sql statement and destroys it when it is deconstructed.
 	//Has move semantics.
 	class sql : public std::unique_ptr<Icompiled_sql> {
 	public:
 		class monostate {};
+		sql() = delete;
 		sql(ISqlite3* p, const char* sz) :std::unique_ptr<Icompiled_sql>(sqlite3_prepare(p, sz)) {}
-		sql(const std::unique_ptr<ISqlite3>& p, const char* sz) :std::unique_ptr<Icompiled_sql>(sqlite3_prepare(p.get(), sz)) {}
+		sql(const std::unique_ptr<ISqlite3>& p, const char* sz);
 		//	copy constructor
 		sql(const sql& a) = delete;
 		//	move constructor
-		sql(sql&& p) noexcept :std::unique_ptr<Icompiled_sql>(p.release()) { }
+		sql(sql&& p) noexcept;
 		//	copy assignment
 		sql& operator=(const sql) = delete;
 		//	Move assignment
-		sql& operator=(sql&& p) noexcept {
-			std::unique_ptr<Icompiled_sql>::reset(p.release());
-		}
-		sql(Icompiled_sql* p) :std::unique_ptr<Icompiled_sql>(p) {}
-		sql(std::unique_ptr<Icompiled_sql>&& p) :std::unique_ptr<Icompiled_sql>(p.release()) { }
+		sql& operator=(sql&& p) noexcept;
+		sql(Icompiled_sql* p);
+		sql(std::unique_ptr<Icompiled_sql>&& p);
 		~sql() = default;
+
 		template <typename T>auto column(int i) const {
 			if constexpr (ro::blob_type<T>) {
 				auto st = (*this)->Isqlite3_column_blob(i);

src/display_wallet.cpp

@@ -1,23 +1,19 @@
 #include "stdafx.h"
 using ro::base58;
 static constexpr char SrcFilename[]{ "src/display_wallet.cpp" };
+
 display_wallet::display_wallet(wxWindow* parent, wxFileName& walletfile) :
 	wxPanel(parent, myID_WALLET_UI, wxDefaultPosition, wxDefaultSize, wxTAB_TRAVERSAL, wxT("Wallet")),
-	m_db(nullptr), m_DisplayWalletEditMenu(1)
+	m_db(walletfile), m_DisplayWalletEditMenu(1),
+	m_read_names_and_keys(m_db, R"|(SELECT * FROM "UserZookoIDs"; )|"),
+	m_read_from_misc(m_db),
+	m_find_position(m_db, R"|( SELECT COUNT(*) FROM UserZookoIDs WHERE LOWER("name")<LOWER(?1) AND "name"<?1;)|")
 {
 	wxLogMessage(wxT("Loading %s"), walletfile.GetFullPath());
 	try {
-		if (!walletfile.IsOk() || !walletfile.HasName() || !walletfile.HasExt()) throw MyException("unexpected file name", __LINE__, __func__, SrcFilename);
-		if (!walletfile.FileExists())throw MyException(
-			walletfile.GetFullPath().append(" does not exist.").ToUTF8(),
-			__LINE__, __func__, SrcFilename);
-		m_db.reset(Sqlite3_open(walletfile.GetFullPath().ToUTF8()));
-		m_insert_name.reset(new sql_insert_name(m_db));
-		m_read_from_misc.reset(new sql_read_from_misc(m_db));
-		m_read_names_and_keys.reset(new ro::sql(m_db, R"|(SELECT * FROM "UserZookoIDs" )|"));
-		if (!(*m_read_from_misc)(1) || m_read_from_misc->value<int64_t>() != WALLET_FILE_IDENTIFIER)throw MyException(sz_unrecognizable_wallet_file_format);
-		if (!(*m_read_from_misc)(2) || m_read_from_misc->value<int64_t>() != WALLET_FILE_SCHEMA_VERSION_0_0 || !(*m_read_from_misc)(4))throw MyException(sz_unrecognized_wallet_schema);
-		m_MasterSecret= *(m_read_from_misc->value<ristretto255::scalar>());
+		if (!m_read_from_misc(1) || m_read_from_misc.value<int64_t>() != WALLET_FILE_IDENTIFIER)throw MyException(sz_unrecognizable_wallet_file_format);
+		if (!m_read_from_misc(2) || m_read_from_misc.value<int64_t>() != WALLET_FILE_SCHEMA_VERSION_0_0 || !m_read_from_misc(4))throw MyException(sz_unrecognized_wallet_schema);
+		m_MasterSecret= *(m_read_from_misc.value<ristretto255::scalar>());
 		ILogMessage(std::format("\t\tmaster secret: #{}", ro::base58(m_MasterSecret).operator const char* ()).c_str());
 		if(!m_MasterSecret.valid()) throw MyException(sz_cold_wallets_not_yet_implemented, __LINE__, __func__, SrcFilename);
 		auto sizer = new wxBoxSizer(wxHORIZONTAL);
@@ -102,10 +98,10 @@ void display_wallet::refresh_from_database() {
 	m_lsizer->Clear(true);
 	m_rsizer->Clear(true);
 	try {
-		m_read_names_and_keys->reset();
-		while (m_read_names_and_keys->step() == Icompiled_sql::ROW) {
-			std::string name = m_read_names_and_keys->column<const char*>(0);
-			auto pubkey = *(m_read_names_and_keys->column<ristretto255::point>(1));
+		m_read_names_and_keys.reset();
+		while (m_read_names_and_keys.step() == Icompiled_sql::ROW) {
+			std::string name = m_read_names_and_keys.column<const char*>(0);
+			auto pubkey = *(m_read_names_and_keys.column<ristretto255::point>(1));
 			if (m_MasterSecret(name).timesBase() != pubkey)throw MyException(std::string(sz_public_key_of) + name + sz_fails_to_correspond);
 			m_lSizer->Add(
 				new wxStaticText(

src/display_wallet.h

@@ -6,10 +6,11 @@ public:
 	~display_wallet();
 private:
 	typedef MenuLink<display_wallet> MenuLink;
-	std::unique_ptr<ISqlite3> m_db;
-	std::unique_ptr <sql_read_from_misc> m_read_from_misc;
-	std::unique_ptr <ro::sql> m_read_names_and_keys;
+	ro::dbconnect m_db;
+	sql_read_from_misc m_read_from_misc;
+	ro::sql m_read_names_and_keys;
 	std::unique_ptr <sql_insert_name> m_insert_name;
+	ro::sql m_find_position;
 
 	ristretto255::CMasterSecret m_MasterSecret;
 	wxBoxSizer* m_lSizer;