[Templates] I swear they hate me.

I can't seem to get these to link lately.

Code:

/*  CheckAlloc
 *  A convenience function to save writing the same "check pointer" code
 *  after having attempted to allocate memory through new.
 */
template <class T> void CheckAlloc( T* ptr )
{
    if ( !ptr )
        ErrorLogging::Log( "CheckAlloc: Failed - memory exhausted?", true );
}

(Feel free to rip at the idea of this CheckAlloc thing - I need feedback!)

I get this link error (good ol' 2019):

Code:

Cvars.obj : error LNK2019: unresolved external symbol "void __cdecl CheckAlloc<struct Cvar>(struct Cvar *)" (??$CheckAlloc@UCvar@@@@YAXPAUCvar@@@Z) referenced in function "struct Cvar * __cdecl MakeCvar(unsigned long,long,float,double,unsigned char,bool,char *)" (?MakeCvar@@YAPAUCvar@@KJMNE_NPAD@Z)

If I defined that, wouldn't I be specialising?

Unless you are using an old, non-standard compiler, new will throw an exception if it fails to allocate memory, so you don't need to check for null anyway. A better way might be to overload new to do what you want.

As far as the linker error, as long as that function is defined in a header included by the source file that defines MakeCvar, it should work.

Ah I see. Thankies.
I'm uncomfortable with try and catch blocks. I always end up using them "C-style" and it ends up making a terrible mess. Observe:

Code:

try
{
    // this
}
catch ( /* whatever*/ )
{
    // handle it
}

^ For every block of code that could fail.

Actually I recall something that could help, new_handler or something (?). Would that be a better solution?

There is a std::set_new_handler function. I don't know much about it, though

God bless MSDN Jan 2004.


(I need to update. I could just use the online one, but F1 is more convenient than click click click type type typesomemore).

You could use nothrow new. That returns NULL instead of throwing an exeption.