Alexander Klenin wrote:
From: Andrew Ford <[EMAIL PROTECTED]>
I am just delving into Template::Filters to add an enhancement to the latex/pdf filter, namely to rerun latex/pdflatex if there are undefined references after the first run.
Yes, I have also used CGI and TT with latex filter in a similiar scenario, and the enhancements you listed below would be very welcome ;)
* set the TEXINPUTS environment variable to include the directory the template was found in, so that file inclusion (in latex) picks up files in that directory (the template is copied to a temporary directory and latex is run in that directory so that temporary files can be cleaned up after the template has been filtered).
Or perhaps a more generic mechanism for setting arbitrary environment variable. Also of value would be a possibility to set some TeX variables, like \graphicspath{} from graphics package, but I do not see a good way to implement this.
[...]
"tmpdir" to specify a 'temporary' directory for debugging -- this would not be deleted by tt2 after processing the template, so that one could go in and sort out latex problems
Also sometimes I wished for an 'output_errors' option which would output TeX errors to a given file (or instead of normal template output), so that it can be easier obtained remotely.
A warning when the filter output is written to a text-mode stream would be useful for a newbies, who (like me) forget to put binmode=>1 in process directive.
I am still at the planning stage for this and would welcome comments and suggestions.
I am not a TT developer, but from the general spirit of TT I would suggest to investigate the idea of generic Template::Filter::External.
Such a filter could set environment varialbes, write per-filter text to a temp file, execute one or more external programs, than read their output and return it as a filtered text.
After that, latex filter can be implemented as a special case. Another application which immediately comes on mind is DocBook and other similiar document generators. Still other is an auto-packaging feature for generating archived downloads on demand.
I'm thinking that I'll adopt a two-pronged approach. I'll patch the latex filter in Template::Filters to Do What I Mean, while providing backwards compatibility, and think about a more general external process plugin, which could be a separate module.
The latex plugin could be patched to run conditionally bibtex and makeindex as well as running latex multiple times. No additional options are required. The log would be:
1. run latex on the text, aborting on errors
2. if latex warns of unresolved references (latex exits with status 0 but reports "LaTeX warning: there were undefined references") then run latex again, aborting on errors
3. if the log file contains lines "LaTeX warning: Citation `xxx' on page N undefined" then run bibtex (if it can be found)
4. if the temporary directory contains a ".idx" file then run makeindex (if it can be found)
5. if bibtex or makeindex were run then run latex again, aborting on errors
6. if latex was rerun in step 5 and the latex log file contains "LaTeX warning: Label(s) may have changed. Rerun to get cross-references right." then rerun latex.
This will handle most simple requirements. For simple LaTeX docuements with no indexes or citations and no forward references the filter will behave as it does now, just running latex once. If the document does make use of LaTeX's bibliographic or indexing facilities or uses forward references then the filter will transparently run the appropriate programs. I won't complicate matters at this stage by adding options to add directories to the TEXINPUTS environment variable or such like. This can be done by setting the variable appropriately on the command line or in the makefile when ttree is invoked, or in the program invoking Template->process.
I'll have a think about Alexander's idea of a generic external filter (or probably plugin) to handle more complex scenarios.
Any more thoughts anyone?
Andrew --
Andrew Ford, Director Pauntley Prints / Ford & Mason Ltd
[EMAIL PROTECTED] South Wing Compton House pauntley-prints.co.uk Compton Green, Redmarley Tel: +44 1531 829900
ford-mason.co.uk Gloucester GL19 3JB Fax: +44 1531 829901
refcards.com/cronolog.org Great Britain Mobile: +44 7785 258278
_______________________________________________ templates mailing list [EMAIL PROTECTED] http://lists.template-toolkit.org/mailman/listinfo/templates
