Daily Unreal Column #28 - Log category as a struct

We all know what log category is and how to use it when logging things to the output log. But, did you know that the log category is actually a struct and has it's own properties?

If we take a look at what the DECLARE_LOG_CATEGORY_EXTERN macro implementation we can see it's actually making a declaration of a struct:

#define DECLARE_LOG_CATEGORY_EXTERN(CategoryName, DefaultVerbosity, CompileTimeVerbosity) \  
    extern struct FLogCategory##CategoryName : public FLogCategory<ELogVerbosity::DefaultVerbosity, ELogVerbosity::CompileTimeVerbosity> \  
    { \  
       FORCEINLINE FLogCategory##CategoryName() : FLogCategory(TEXT(#CategoryName)) {} \  
    } CategoryName;

and... The struct inherits from FLogCategory and further down from the FLogCategoryBase.

This means that you can use the defined struct just like any other property. For example, you can check whether this category logs should be suppressed or not by calling:

if (LogTemp.IsSuppressed(ELogVerbosity::Verbose))
{
	// Do stuff
}