git diff & add combined

gitconfig

[alias]
    da = "! addprev() { while true; do \
          read -p \"Do you wish to add this file? ([Y]es, [N]o, [P]atch)\" yn ; \
          case $yn in \
          [Yy]* ) git add $1; break;; \
          [Pp]* ) git add -p $1; break;; \
          [Nn]* ) exit;; \
          * ) echo "Please answer yes, no or patch.";; \
          esac \
        done } ; \
        gotoUsedDirectory() { \
        if [ -n \"${GIT_PREFIX}\" ]; then \
          cd ${GIT_PREFIX} ; \
        fi \
        } ; \
        echo \"$1\" ; \
        gotoUsedDirectory && git diff $1 && addprev $1"