>bash --version
GNU bash, version 4.3.48(1)-release (x86_64-slackware-linux-gnu)
Copyright (C) 2013 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>

This is free software; you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
>perl -MString::ShellQuote=shell_quote -E 'say shell_quote("!","FOO=BAR","baz")'
! FOO=BAR baz
>! FOO=BAR baz
-bash: baz: command not found
>'!' FOO=BAR baz
-bash: !: command not found
>! 'FOO=BAR' baz
-bash: FOO=BAR: command not found
>