From 0eafe754447fa6c373d1a13e4e590488db82a007 Mon Sep 17 00:00:00 2001
From: Killili <jan@himmelmann.me>
Date: Fri, 6 May 2016 15:15:41 +0200
Subject: [PATCH 1/2] null support | header + test

---
 .../extensions/null_support.h                 | 29 ++++++++++++++++
 tests/null_value.cc                           | 33 +++++++++++++++++++
 2 files changed, 62 insertions(+)
 create mode 100644 hdr/sqlite_modern_cpp/extensions/null_support.h
 create mode 100644 tests/null_value.cc

diff --git a/hdr/sqlite_modern_cpp/extensions/null_support.h b/hdr/sqlite_modern_cpp/extensions/null_support.h
new file mode 100644
index 00000000..4af6c4b7
--- /dev/null
+++ b/hdr/sqlite_modern_cpp/extensions/null_support.h
@@ -0,0 +1,29 @@
+#pragma once
+
+using namespace sqlite;
+using namespace std;
+
+namespace sqlite {
+	// custom null value
+	struct null_value {
+		bool value = true;
+		void operator=(bool val) { value = val; }
+		operator bool() const { return value; }
+	};
+
+	template<> inline database_binder::chain_type& operator <<(database_binder::chain_type& db, const sqlite::null_value& val) {
+		int hresult;
+		if((hresult = sqlite3_bind_null(db->_stmt.get(), db->_inx)) != SQLITE_OK) {
+			exceptions::throw_sqlite_error(hresult);
+		}
+		++db->_inx;
+		return db;
+	}
+	template<> inline void get_col_from_db(database_binder& db, int inx, sqlite::null_value& d) {
+		if(sqlite3_column_type(db._stmt.get(), inx) == SQLITE_NULL) {
+			d = true;
+		} else {
+			d = false;
+		}
+	}
+}
\ No newline at end of file
diff --git a/tests/null_value.cc b/tests/null_value.cc
new file mode 100644
index 00000000..f09798a3
--- /dev/null
+++ b/tests/null_value.cc
@@ -0,0 +1,33 @@
+#include <iostream>
+#include <string>
+#include <sqlite_modern_cpp.h>
+#include <sqlite_modern_cpp/extensions/null_support.h>
+
+int main() {
+
+	try {
+		database db(":memory:");
+		db << "CREATE TABLE tbl (id integer, name string);";
+		db << "INSERT INTO tbl VALUES (?, ?);" << 1 << "hello";
+		db << "INSERT INTO tbl VALUES (?, ?);" << 2 << null_value();
+
+		db << "select id,name from tbl where id = 1" >> [](int id, null_value name_null) {
+			if(name_null) exit(EXIT_FAILURE);
+		};
+
+		db << "select id,name from tbl where id = 2" >> [](int id, null_value name_null) {
+			if(!name_null) exit(EXIT_FAILURE);
+		};
+
+
+	} catch(sqlite_exception e) {
+		cout << "Sqlite error " << e.what() << endl;
+		exit(EXIT_FAILURE);
+	} catch(...) {
+		cout << "Unknown error\n";
+		exit(EXIT_FAILURE);
+	}
+
+	cout << "OK\n";
+	exit(EXIT_SUCCESS);
+}

From 864a1a02163baec9793af3d486e89fd3f8e52fac Mon Sep 17 00:00:00 2001
From: Killili <jan@himmelmann.me>
Date: Fri, 6 May 2016 15:44:36 +0200
Subject: [PATCH 2/2] ignore unused variable

---
 hdr/sqlite_modern_cpp/extensions/null_support.h | 4 ++++
 tests/null_value.cc                             | 2 ++
 2 files changed, 6 insertions(+)

diff --git a/hdr/sqlite_modern_cpp/extensions/null_support.h b/hdr/sqlite_modern_cpp/extensions/null_support.h
index 4af6c4b7..01a8db9f 100644
--- a/hdr/sqlite_modern_cpp/extensions/null_support.h
+++ b/hdr/sqlite_modern_cpp/extensions/null_support.h
@@ -11,6 +11,8 @@ namespace sqlite {
 		operator bool() const { return value; }
 	};
 
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wunused-variable"
 	template<> inline database_binder::chain_type& operator <<(database_binder::chain_type& db, const sqlite::null_value& val) {
 		int hresult;
 		if((hresult = sqlite3_bind_null(db->_stmt.get(), db->_inx)) != SQLITE_OK) {
@@ -19,6 +21,8 @@ namespace sqlite {
 		++db->_inx;
 		return db;
 	}
+#pragma GCC diagnostic pop
+
 	template<> inline void get_col_from_db(database_binder& db, int inx, sqlite::null_value& d) {
 		if(sqlite3_column_type(db._stmt.get(), inx) == SQLITE_NULL) {
 			d = true;
diff --git a/tests/null_value.cc b/tests/null_value.cc
index f09798a3..e2a928db 100644
--- a/tests/null_value.cc
+++ b/tests/null_value.cc
@@ -12,10 +12,12 @@ int main() {
 		db << "INSERT INTO tbl VALUES (?, ?);" << 2 << null_value();
 
 		db << "select id,name from tbl where id = 1" >> [](int id, null_value name_null) {
+			cout << "Name should not be null for ID:" << id;
 			if(name_null) exit(EXIT_FAILURE);
 		};
 
 		db << "select id,name from tbl where id = 2" >> [](int id, null_value name_null) {
+			cout << "Name should be null for ID:" << id;
 			if(!name_null) exit(EXIT_FAILURE);
 		};