Find shortest string in an array with bash

shortest.sh

#!/bin/bash

shortest()
{
  local arrayname=${1:?Array name required} varname=${2:-shortest}
  local IFS= string e

  eval "array=( \"\${$arrayname[@]}\" )"
  shortest=${array[0]}
  for e in "${array[@]}"; do
    [[ ${#e} -lt ${#shortest} ]] && shortest=$e
  done
  [[ "$varname" != shortest ]] && eval "$varname=${shortest}"
}

declare -a toto=( s1.free.domain.org free.domain.org s2.free.domaine.org )
shortest toto
echo $shortest