A strange ASSERT is triggered when trying to cast an object that has multiple opCast operators for differents types:

2>  Assertion failed: func->returnType.GetTokenType() == ttVoid && func->parameterTypes.GetLength() == 1 && func->parameterTypes[0].GetTokenType() == ttQuestion, file ..\..\source\as_scriptengine.cpp, line 4918

Having a look at the code it seems this assertion is not valid and should be replaced by an if() statement - otherwise it means that you cannot implement the opCast method with different return types.

	// Look for ref cast behaviours
	asCScriptFunction *universalCastFunc = 0;
	asCObjectType *from = reinterpret_cast<asCObjectType*>(fromType);
	for( asUINT n = 0; n < from->methods.GetLength(); n++ )
	{
		asCScriptFunction *func = scriptFunctions[from->methods[n]];
		if( func->name == "opImplCast" ||
			(!useOnlyImplicitCast && func->name == "opCast") )
		{
			if( func->returnType.GetTypeInfo() == toType )
			{
				*newPtr = CallObjectMethodRetPtr(obj, func->id);
				// The ref cast behaviour returns a handle with incremented
				// ref counter, so there is no need to call AddRef explicitly
				// unless the function is registered with autohandle
				if( func->sysFuncIntf->returnAutoHandle )
					AddRefScriptObject(*newPtr, toType);
				return asSUCCESS;
			}
           // FIXME: check if this is a universal cast operator before storing it instead of asserting
			else if(func->returnType.GetTokenType() == ttVoid &&
                func->parameterTypes.GetLength() == 1 &&
                func->parameterTypes[0].GetTokenType() == ttQuestion )
			{
				universalCastFunc = func;
			}
		}
	}

I have tested the fix above and it seems to be causing no issues (and actually I think it fixes problems in case no appropriate cast is found). What do you think?

Thanks for the report. I'll look into this and have it fixed.

Great, thanks!

Your solution is correct.

I've checked in this in revision 2539.

Thanks!