worldspawn/libs/generic/static.cpp

/*
   Copyright (C) 2001-2006, William Joseph.
   All Rights Reserved.

   This file is part of GtkRadiant.

   GtkRadiant is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.

   GtkRadiant is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with GtkRadiant; if not, write to the Free Software
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */

#include "static.h"
#include "globaldefs.h"

#if GDEF_DEBUG || defined( DOXYGEN )

namespace ExampleStatic
{
// Static example
// ---- myclass.h
class MyClass
{
public:
int value;
MyClass() : value( 3 ){
}
};

typedef Static<MyClass> StaticMyClass;

// ---- main.cpp
class DynamicInitialisation
{
public:
DynamicInitialisation(){
	// StaticMyClass::instance() may be invalid here because construction order is undefined
}
};

DynamicInitialisation g_dynamicInitialisation;

void duringMain(){
	int bar = StaticMyClass::instance().value;
}
// end example
}

namespace ExampleLazyStatic
{
// LazyStatic example
// ---- myclass.h
class MyClass
{
public:
int value;
MyClass() : value( 3 ){
}
// destructor will never be called
};

typedef LazyStatic<MyClass> StaticMyClass;

// ---- main.cpp
class DynamicInitialisation
{
public:
DynamicInitialisation(){
	int bar = StaticMyClass::instance().value;
}
};

DynamicInitialisation g_dynamicInitialisation;

void duringMain(){
	int bar = StaticMyClass::instance().value;
}
// end example
}

namespace ExampleSmartStatic
{
// SmartStatic example
// ---- myclass.h
class MyClass
{
public:
int value;
MyClass() : value( 3 ){
}
};

typedef CountedStatic<MyClass> StaticMyClass;

// ---- main.cpp
class DynamicInitialisation
{
public:
DynamicInitialisation(){
	// StaticMyClass::instance() is invalid before the ref is constructed
	SmartStatic<MyClass> ref;
	int bar = ref.instance().value;

	SmartStatic<MyClass> ref2;   // any number of instances are allowed.
}
};

DynamicInitialisation g_dynamicInitialisation;

void duringMain(){
	int bar = SmartStatic<MyClass>().instance().value; // an instance can be a temporary
}
// end example
}

#endif