source: vendor/bash/3.1/tests/nquote3.tests

a=$'a\001b'

set $a

b=$a
c=$1
d="$1"

e=$'uv\001\001wx'
f=$'uv\001w\001xy'

set $e $e

recho ${e%%??}
recho "${e%%??}"

recho ${e%%???}
recho "${e%%???}"

recho ${a#?}
recho "${a#?}"

# simple variables

recho ${f##*$'\001'}
recho "${f##*$'\001'}"
recho ${f##*''}                # literal ^A
recho "${f##*'^A'}"             # two characters, `^' and `A'

recho ${e%$'\001'*}
recho "${e%$'\001'*}"
recho ${e#*$'\001'}
recho "${e#*$'\001'}"

# array members

arr[0]=$e
arr[1]=$f

recho ${arr[1]##*$'\001'}
recho "${arr[1]##*$'\001'}"
recho ${arr[1]##*''}           # literal ^A
recho "${arr[1]##*'^A'}"        # two characters, `^' and `A'

recho ${arr[0]%$'\001'*}
recho "${arr[0]%$'\001'*}"
recho ${arr[0]#*$'\001'}
recho "${arr[0]#*$'\001'}"

recho ${arr%$'\001'*}
recho "${arr%$'\001'*}"
recho ${arr#*$'\001'}
recho "${arr#*$'\001'}"

# positional parameters

set $e $f

recho ${2##*$'\001'}
recho "${2##*$'\001'}"
recho ${2##*''}                # literal ^A
recho "${2##*''}"              # literal ^A
recho ${2##*'^A'}               # two characters, `^' and `A'
recho "${2##*'^A'}"             # two characters, `^' and `A'

recho ${1%$'\001'*}
recho "${1%$'\001'*}"
recho ${1#*$'\001'}
recho "${1#*$'\001'}"

recho ${@%$'\001'*}
recho "${@%$'\001'*}"
recho ${@#*$'\001'}
recho "${@#*$'\001'}"
recho ${@##*''}                # literal ^A
recho "${@##*'^A'}"             # two characters, `^' and `A'

# arrays treated as a whole

recho ${arr[@]%$'\001'*}
recho "${arr[@]%$'\001'*}"
recho ${arr[@]#*$'\001'}
recho "${arr[@]#*$'\001'}"
recho ${arr[@]##*''}           # literal ^A
recho "${arr[@]##*'^A'}"                # two characters, `^' and `A'