Lightning-fast project-wide find/replace with git grep and sed

.profile fragment

  gg_replace() {
    if [[ "$#" == "0" ]]; then
      echo 'Usage:'
      echo '  gg_replace term replacement file_mask'
      echo
      echo 'Example:'
      echo '  gg_replace cappuchino cappuccino *.html'
      echo
    else
      find=$1; shift
      replace=$1; shift

      ORIG_GLOBIGNORE=$GLOBIGNORE
      GLOBIGNORE=*.*
      
      if [[ "$#" = "0" ]]; then
        set -- ' ' $@
      fi

      while [[ "$#" -gt "0" ]]; do
        for file in `git grep -l $find -- $1`; do
          sed -e "s/$find/$replace/g" -i'' $file
        done
        shift
      done

      GLOBIGNORE=$ORIG_GLOBIGNORE
    fi
  }
  gg_dasherize() {
    gg_replace $1 `echo $1 | sed -e 's/_/-/g'` $2
  }