Preprocessor symbol for maximal number of arguments

QMetaMethod::invoke (and related) overloads take up to 10 arguments.

But that seems to be nowhere specified as a const/enum value or as a preprocessor symbol. While having such a symbol would be useful when writing some generic code.

Sure, I can make a @#define myself but it seems far more natural place for such is the Qt library itself. In sources it seems to use alike solutions. So why no make it public?