For a number of days I've been confused with some problems I had when using the \pdftex_if_engine:TF switch in a LaTeX3/expl3 class of my own. I thought it would be equivalent to the \ifpdf switch, ...
I'm creating rather complicated diagram and would like to put all the controls all in one easy to find location and not scattered throughout the document. To do this, I've created setter and getter ...
I want to create a pspicture with a variety of parameters which are interdependent. I'm using expl3 for the interface. But I get an error when I try to use \getr Error: /undefined in \getr Operand ...