ghost-in-the-shell.sh

#!/bin/sh

#  -n STRING
#        the length of STRING is nonzero

foo=""

echo "expect: no output (syntax error)"
if [ -n "${foo}"]
then
  echo "1. [ -n "${foo}"]"
fi

echo "expect: no output"
if [ -n "${foo}" ]
then
  echo "2. [ -n "${foo}" ]"
fi

foo="true"

echo "expect: no output (syntax error)"
if [ -n "${foo}"]
then
  echo "3. [ -n "${foo}"]"
fi

echo "expect: output"
if [ -n "${foo}" ]
then
  echo "4. [ -n "${foo}" ]"
fi