1 files changed, 4 insertions, 1 deletions

diff --git a/makefile b/makefile
index 435f88f..eba7b62 100644
--- a/makefile
+++ b/makefile
@@ -1,3 +1,6 @@
+exts := md png sh bib tex
+findopts := $(foreach ext,$(exts),-or -iname "*.$(ext)")
+
 all: pdf
 
 pdf: clean
@@ -12,7 +15,7 @@ pdf: clean
 clean:
         rm -rf .backup
         find -iname "*~" | xargs rm -rf
-        find ./* -type f | grep 'makefile\|\.md$$\|\.png$$\|\.sh$$\|\.bib$$\|\.tex$$' > ls-R
+        find ./* -type f -iname "makefile" $(findopts) > ls-R
         rsync -avPr --files-from=ls-R . .backup
         rm -rf *
         cp -p -r .backup/* .