add support difflatex-svn

[shiblon]

Originally reported on Google Code with ID 148

I use latex-makefile in version-controlled directories and frequently produce diffed
versions of documents (using difflatex), most often against older revisions of a document
(using difflatex' subversion support: difflatex-svn). 

It would be extremely convenient if the makefile had in-built support for goals like

document.diff-r123.pdf 
to produce a diff-annotated pdf against revision 123 from the repository.

Reported by timobaumann on 2012-01-14 15:05:22

[shiblon]

the command that I use is actually called latexdiff, not difflatex (which also exists
but doesn't work as well)

Reported by timobaumann on 2012-01-14 15:07:37

[shiblon]

Thanks for the report.  I've been slow to respond because of my day job.  :-)

Unfortunately, I still have a day job, so I'll still be somewhat slow getting to this.

While we're waiting for me to get around to it, though, could you give some more detail
about the steps that you take to do diffs?   A sequence of commands would be useful.
 Then we can probably devise something to stick into Targets.ini as a temporary workaround
and a way of testing our solution.

Reported by shiblon on 2012-03-22 06:37:05

• Labels added: Type-Enhancement, Priority-Low
• Labels removed: Type-Defect, Priority-Medium

[shiblon]

Sorry for replying so late. Actually, the following in my Targets.ini works marvelously:

%-diffPREV.tex : %.tex
        latexdiff-svn -r PREV $<

I don't know whether you'd want this capability directly in the program, if not then
a wiki page for common extensions to the Makefile would probably be good enough.

Reported by timobaumann on 2013-03-19 14:34:14

[timobaumann]

I took the freedom to add the proposed fix to https://github.com/shiblon/latex-makefile/wiki/LaTeX-Makefile-Recipes