pgfkeyx – Extended and more robust version of pgfkeys

The pack­age ex­tends and im­proves the ro­bust­ness of the pgfkeys pack­age. In par­tic­u­lar, it can deal with ac­tive comma, equal­ity sign, and slash in key pars­ing. The dif­fi­culty with ac­tive char­ac­ters has long been a prob­lem with the pgfkeys pack­age.
The pack­age also in­tro­duces han­dlers be­yond those that pgfkeys can of­fer.