:

diff --git a/Makefile b/Makefile
index 27f2a1b0c2a353fcc7ca2d4967013456fd0f4f75..3928876c3866e87acd5bddd712da2cb285aca97e 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -7,7 +7,7 @@ build: ensure
 book: build
 
 deploy: book
-       @$(shell git push origin :gh-pages || true)
+       @git branch | grep gh-pages && git push origin :gh-pages || true
        @git add -f book
        @git commit -m "add book"
        @git subtree push --prefix book origin gh-pages