Git: How to delete all the merged branches

Who has a repository without dead already merged branches? Admit it, almost no one. In my team, especially since we decided to move to git flow^[1], this ideal situation rarely happens. It is not that uncommon forget to delete a merged branch from remote, it happens to everyone. But

I believe a tidy repository should give you the possibility to have a look at its status just with a glance.

After some research I ended up with the following command to delete all your merge branches in one go:

git branch -r --merged | 
grep origin | 
grep -v '>' | 
grep -v master | 
xargs -L1 | 
cut -d"/" -f2- | 
xargs git push origin --delete

PS: Be careful to use the correct branch as reference, once I deleted develop by mistake :D