Bash script to toggle xdebug on/off on Mac OS X running PHP installed from Homebrew

xdebug

#!/bin/bash

XDEBUG_INI_PATH="/usr/local/etc/php/7.0/conf.d/ext-xdebug.ini"

function turn_off {
    `sed -i '' 's/^zend_extension/#zend_extension/g' $XDEBUG_INI_PATH`
}

function turn_on {
    `sed -i '' 's/^#zend_extension/zend_extension/g' $XDEBUG_INI_PATH`
}

CURRENT=`cat $XDEBUG_INI_PATH | grep xdebug.so`
if [[ $CURRENT =~ ^#zend_extension ]];
then
    echo 'Xdebug is currently off'
    CHANGE_TO='on'
else
    echo 'Xdubug is currently on'
    CHANGE_TO='off'
fi

if [[ ${1+x} ]];
then
    if [[ ! $1 =~ ^o(n|ff)$  ]];
    then
        echo "Invalid argument: $1. Valid arguments are \`on\` and \`off\`.";
    else
        echo "Turning xdebug $1";
        eval turn_${1}
    fi
else
    echo "Turning xdebug $CHANGE_TO"
    eval turn_${CHANGE_TO}
fi