Bash Positional Option Parsing with rvalue assignment

positional_params.sh

#!/bin/bash

POSITIONAL=( )
for item; do
    rvalue="${item#*=}"

    [[ "$item" == --help     ]] && SHOWHELP=1       && continue
    [[ "$item" == --force    ]] && FORCE=1          && continue
    [[ "$item" == --force=*  ]] && FORCE=$rvalue    && continue

    [[ "$item" == --*        ]] && {
      >&2 echo "unrecognized option: $item"
      CLI_ERROR=1
      continue
    }

    POSITIONAL+=( "$item" )
done

set -- "${POSITIONAL[@]}"

if (( SHOWHELP )); then
	echo ""
	exit 0
fi

(( CLI_ERROR )) && exit 1