git alias to edit repo files using sed

.gitconfig

[alias]
        # use sed to edit files from 'git ls-files' in-place using the editing expression
        # git sed [ args-to-git-ls-files ] <sed-expr>
        # git sed s/foo/bar/g
        # git sed --modified s/foo/bar/g
        # handles nasty file names, e.g. with whitespaces, punctuation etc
        sed = "!f() { let n=$#-1; let n=$((n>0?n:0)); eval sed -i ${@: -1} $(git ls-files ${@: 1:$n} | awk '{printf(\"\\\"%s\\\"\\n\", $0)}'); }; f"