Pawel Jackowski wrote:
Hi Hans!
thanks for response.
Hello,
I suppose the issue was discussed before but couldn't find that is archives.
Making high level macros in (pure) TeX encounters problem of optionality[...]
in the previosu century taco made some extensiong dealing with key/val parsing (and other kinds of parsing); at that time we did quite some testing with speed issues, and the price to pay was higher that the gain; keep in mind that in tex catcodes and expansion always kind of interfere in such things;
Indeed, to keep things consistent, parameter text should always be expanded before being swallowed by \macro... Anyway, pdfTeX handles that somehow, supporting both expansion and catcoding.
parsing keys as in \hrule ... is kind of special anyway: one can overload (repeat specs) but not all of them are treated the same; fuzzy optimizations and such; so there is not much reusable code there
ok, if you limit key/val parsing to 'strings' only (i.e. no expansion, no catcode support) then it can be faster, but at the same time it also becomes useless for everyday usage; as with more tex things, because tex is rather optimized, hard coded alternatives (extensions to the language) not always pay off; also consider implementation issues like namespacing, scope of keys, etc
...and parameters handling rules in such an extention would probably be faaaar away from TeX. But if tries has been made in previous century, meybe it's high time to repeat tests? In the previous century features such as decompressing/recompressing PNG in runtime didn't pay off either. If you don't consider it doable, I will reopen the request in the next century. -)
sure, but there 'new methods' pop up and or constraints disappear (mem); tex is really optimized (i did lots of timing and many low level context commands and k/v handling are optimized to the max); on the other hand, the bigger memory makes it possible to be a bit more spending that in the past, i.e. write less fuzzy code (much tex code is fuzzy because of speed and mem issues); btw, one reason for context being 'slow' was that it had all this key value etc stuff and used quite some hash and mem; recently there was a report of on the tex live list who mentioned latex being much slower than in the past and tacos answer to that was that it's not related to slower pdftex or so since context had not become slower: it was just that bigger (la)tex's take more time to initialize, etc etc and all packages become bigger; if you want to speed up macro packages think of what happens in there: even in a parameter driven package like context, the amount of expanded code (tracingall) with regards to k/v handling is small compared to messing around with boxes (esp when \copy is used) and saving/restoring as well as redundant passing around arguments (the #1 things) another think to keep in mind: when discussing things like reimplementing tex, one can be tricked into thinking that there should be fast methods for char handling, hyphenation, etc etc (i.e. influences design of for instance classes in oo like aproaches); however, in more modern macro package features, tex spends much time in manipulating boxes (lists) in the otr and it could be that modern programming languages provide features that would make such critical operations faster; so, the gain is in other areas (take pdftex: pdf inclusion is incredibly fast, simply because that piece is written in a different language/way); compare it to scripting languages: they excel in handling text simply because they're made with that in mind. Hans