Package: latexpp
Latex preprocessor — apply macro definitions, remove comments, and moreDisclaimer: latexpp is still at an experimental development stage.InstallationYou can installlatexppusingpipdirectly fromlatexpp’s github repo:>pipinstallgit+https://github.com/phfaist/latexpp.gitHow it worksThe latex preprocessorlatexppreads your main latex document and copies it
to an output directory while applying a series of “fixes” that you can
configure.  For instance, you can remove comments, you can include files that
you input with\inputmacros, or you can replace custom macros by their
LaTeX expansion.You runlatexppin a folder with alppconfig.ymlfile that specifies the
necessary information such as the main LaTeX document, the output directory, and
which fixes to apply.Samplelppconfig.yml:# latexpp config for MyDocument.tex## This is YAML syntax -- google "YAML tutorial" to get a quick intro.  Be# careful with spaces since indentation is important.# the master LaTeX document -- this file will not be modified, all output will# be produced in the output_dirfname:'MyDocument.tex'# output file(s) will be created in this directory, originals will not be# modifiedoutput_dir:'latexpp_output'# main document file name in the output directoryoutput_fname:'paper.tex'# specify list of fixes to apply, in the given orderfixes:# replace \input{...} directives by the contents of the included file-'latexpp.fixes.input.EvalInput'# remove all comments-'latexpp.fixes.comments.RemoveComments'# copy any style files (.sty) that are used in the document and that# are present in the current directory to the output directory-'latexpp.fixes.usepackage.CopyLocalPkgs'# copy figure files to the output directory and rename them fig-1.xxx,# fig-2.xxx, etc.-'latexpp.fixes.figures.CopyAndRenameFigs'# Replace \bibliography{...} by \input{xxx.bbl} and copy the bbl file to the# output directory.  Make sure you run (pdf)latex on the main docuemnt# before running latexpp-'latexpp.fixes.bib.CopyAndInputBbl'# Expand some macros. Latexpp doesn't parse \newcommand's, so you need to# specify here the LaTeX code that the macro should be expanded to. If the# macro has arguments, specify the nature of the arguments here in the# 'argspec:' key (a '*' is an optional * character, a '[' one optional# square-bracket-delimited argument, and a '{' is a mandatory argument). The# argument values are available via the placeholders %(1)s, %(2)s, etc. Make# sure to use single quotes for strings that contain \ backslashes.-name:'latexpp.fixes.macro_subst.Subst'config:macros:# \tr         -->  \operatorname{tr}tr:'\operatorname{tr}'# \ket{\psi}  -->  \lvert{\psi}\rangleket:argspec:'{'repl:'\lvert{%(1)s}\rangle'# \braket{\psi}{\phi}  -->  \langle{\psi}\vert{\phi}\ranglebraket:argspec:'{{'repl:'\langle{%(1)s}\vert{%(2)s}\rangle'The config file follows standard YAML syntax (if you’re in doubt, google a YAML
tutorial).Documentation is available atlatexpp.readthedocs.io. You can also explore thelatexpp/fixes/directory for the list of possible fixes.  The documentation is still a little
sparse at the moment (I wrote this preprocessor in the
matter of a few days, and I won’t have tons of time to devote to it). But the
python source is fairly short and should be relatively decipherable.Each fix is specified by a qualified python class name.  For instance,latexpp.fixes.comments.RemoveCommentsinvokes classRemoveCommentsfrom
the python modulelatexpp.fixes.comments.  You can specify custom arguments
to the class constructor by using the syntax with the ‘name:’ and ‘config:’ keys
as shown above.  The keys in each ‘config:’ section are directly passed on to
the class constructor as corresponding keyword arguments.The fixes in thelatexpp/fixes/pkg/directory are those fixes that are
supposed to apply all definitions of the corresponding package in order to
remove a dependency on that package.It’s also straightforward to write your own fix classes to do more complicated
stuff.  Create a python package (a new foldermypackagewith an empty__init__.pyfile) and create a python module (e.g.myfixmodule.py) in
that package that defines your fix class (e.g.MyFix).  You can get
inspiration from one of the simple examples in thelatexpp/fixes/folder.
Set up your$PYTHONPATHso that your python package is exposed to python.
Then simply specify the pacakge/module your fix is located in in the YAML file,
e.g.,mypackage.myfixmodule.MyFixinstead oflatexpp.fixes.xxxxx.YYYY.How it actually worksThelatexpppreprocessor relies onpylatexenc 2.0to parse the latex document into an
internal node structure.  For instance, the chunk of latex code:Hello, \textit{world}! % show a greetingwill be parsed into a list of four nodes, a ‘normal characters node’"Hello, ", a ‘macro node’\textitwith argument a ‘group node’{world}which
itself contains a ‘normal characters node’world, a ‘normal characters node’"! ", and a ‘latex comment node’% show a greeting.  The structure is
recursive, with e.g. macro arguments and environment contents themselves
represented as nodes which can contain further macros and environments.  Seepylatexenc.latexwalkerfor more
information.  Thepylatexenclibrary has a list of some known macros and
environments, and knows how to parse their arguments.  Some fixes inlatexppadd their own macro and environment definitions.Once the latex document is parsed into the node structure, the document is
processed by the given list of fixes. Each fix is called in turn. Each fix
traverses the document node structure and applies any relevant changes.License(C) 2019 Philippe Faist, philippe dot faist <at@at> bluewin dot chMIT Licence, see License.txt