a silly little script to get bash's `trap` function to act a bit like go's `defer` keyword

defer-bash.sh

#!/bin/bash

function defer() {
  existing=$(trap -p EXIT | sed -e "s/^trap -- '\(.*\)' EXIT$/\1/" -e "s/\'\\\'\'/'/g")
  new="$@"

  if [ ! -z "${existing}" ]; then
    existing="${existing} ;"
  fi

  trapCmd="{ ${new} ; ${existing}  }"

  trap "$trapCmd" EXIT
}
defer "echo 'bye'"
defer "echo 'hi'"

echo "this should be first"