More on XeTeX primitives

There has been a bit more work on the idea of adding primitives to XeTeX to match those available in pdfTeX.The list of pdfTeX primitives which look interesting has grown slightly, and now reads:

  • \ifincsname
  • \ifpdfprimitive
  • \pdfprimitive
  • \pdfshellescape
  • \pdfstrcmp

At the same time, it would be useful to include the “extended” version of \vadjust which pdfTeX makes available. This is something that has been asked about before, and as with the rest of the changes the main issue is not the idea of doing it but the time for actual implementation.

The real need to have \pdfstrcmp available for LaTeX3 work means that some effort has actually gone into this. I’ve got no experience with either Pascal or the WEB format, but I’ve managed but dint of determination to get something passable to Jonathan Kew. There will need to be some adjustments, as XeTeX works with UTF-8 internally, which pdfTeX does not do. However, I’m hopeful that we will see new primitives in XeTeX soon.

Quite how the primitives will be named is still to be decided. The existing \pdf... naming does not really make sense with these non-PDF related functions. So they could end up as \XeTeX... or may just be given generic names. I’m leaving that to Jonathan!

3 thoughts on “More on XeTeX primitives

  1. WEB and Pascal are the same language as Donald Knuth says on page X of his Computer & Typesetting/ TeX: the program textbook: (I have read half of the book so hopefully after TUG conference I will continue to read. It is as interesting as TeXBook and he also at the beginning of the book says that the reader should be familar with TeXBook. He explain every single algorithm in TeX and also demonstrates why some specific aspect of TeX are done in certain ways.)

    “A WEB program is a Pascal program that has been cut up into pieces and rearranged into an order that is easier for a human being to understand. A Pascal program is a WEB program that has been rearranged into an order that is easier for a computer to understand.

    In other words, WEB programs and Pascal programs are essentially the same kind of things, but their parts are arranged differently. You should be able to understand a Pascal program better when you see it in its WEB form, if the author of the WEB form has chosen a good order of presentation.

    Before you try to read a WEB program, you should be familar with the Pascal language.”

Leave a Reply