The line you mentioned occurs only in Locator::service(), and in that context, the symbol service is a function pointer to Locator::service() and thus not assignable to the type of the member mService. Furthermore, in Locator::provide(), you're not comparing the argument to null in the if-statement, but you're assigning to it.
Never paraphrase an error message, you should always copy and paste them as they are, because getting even a small detail wrong or missing can greatly change the meaning of the error and the interpretation of the situation. You may then get the wrong answer because we assumed the wrong situation about your code.
EDIT: It gave me compiling errors, nvm.
These are the errors:
Game.obj : error LNK2001: unresolved external symbol "private: static class AudioService * Locator<class AudioService,class NullAudio>::mService" (?mService@?$Locator@VAudioService@@VNullAudio@@@@0PAVAudioService@@A)
1>Game.obj : error LNK2001: unresolved external symbol "private: static class NullAudio Locator<class AudioService,class NullAudio>::nullService" (?nullService@?$Locator@VAudioService@@VNullAudio@@@@0VNullAudio@@A)
and here is the current code:
template<class T, class B>
static void Locator<T,B>::provide(T* service)
if( service == NULL )
Locator<T,B>::mService = &Locator<T,B>::nullService;
Locator<T,B>::mService = service;
static T* service()
if( Locator<T,B>::mService == NULL )
static T* mService;
static B nullService;
Edited by Moonkis, 07 November 2012 - 10:17 AM.