1# $FreeBSD: stable/10/bin/sh/tests/expansion/cmdsubst18.0 315179 2017-03-12 19:49:08Z jilles $ 2 3x=X 4unset n 5r=${x+$(echo a)}${x-$(echo b)}${n+$(echo c)}${n-$(echo d)}$(echo e) 6[ "$r" = aXde ] 7