rename files from a hash of file name mappings

mapfiles

#! /usr/bin/env bash

manifest=${1:-manifest}

[ ! -f "$manifest" ] && echo "no file \"${manifest}\"" && exit 1

while read line
do
  from=${line%%:*}
  to=${line##*:}
  if [ -e "$from" ] && [ ! -e "$to" ]
  then
    echo "${from} -> ${to}"
    mv "$from" "$to"
  else
    echo "no file \"${from}\" or \"${to}\" already exists"
  fi
done < "$manifest"