#!/bin/bash

GLOB="global_var"

function say() {
	_loc="${1:-hello}"
	_res="${_loc} ${GLOB}"

	echo "${_res}" | cut -d" " -f1

	echo 'single quoted string ${_loc} &> must not be expanded' &>/dev/null
}
USELESS_VAR="useless value" with "${GLOB}"
USELESS_VAR="$(echo hello world)"
say world