LaTeX newcommand minimizer

texmin.sh

#!/bin/sh
#
# by Lorenz Hübschle-Schneider and Jori Mäntysalo, 2013-2015
# license: cc-by-sa 3.0
# Based on http://tex.stackexchange.com/a/113156
#
# Remove any unnecessary \newcommand and \renewcommand from a LaTeX file
# and ensure that it still compiles

> notneeded
> needed

out=${2:-tmp}

# determine which commands are not in use
# if you have too many of them you might want to remove the & in line 13 :>
fgrep '\newcommand' $1 | cut -f 2 -d '{' | cut -f 1 -d '}' |
while read a; do
	echo "checking whether command $a is needed";
    egrep -v "\\newcommand\{\\\\$a\}" $1 > ${out}_${a}.tex
    pdflatex -halt-on-error ${out}_${a}.tex &&
        echo $a >> notneeded || echo $a >> needed &
done
wait

# remove unneeded commands
cp $1 ${out}.tex
for a in $(cat notneeded); do
	echo "removing command $a"
    egrep -v "\\(re)?newcommand\{\\\\$a\}" ${out}.tex > ${out}.tmp
    mv ${out}.tmp ${out}.tex
done