@main[]

$s[
	^taint[html][ some <a href="/?a&b">html</a> code ]
	^taint[file-spec][ * ? " | ]
	^taint[ some  <?dirty?>  code ] trailing whitespace here ->   ]

env and args tainting tests:

1. $f[^file::exec[cat^os[-windows].sh; $.HTTP_OK[$s] $.REMOTE_ADDR[allowed];env;HTTP_OK]]
   =$f.text=
2. $f[^file::exec[cat^os[-windows].sh; ;args;$s]]
   =$f.text=
3. $f[^file::exec[cat^os[-windows].sh; ;args;"quo ted"]]
   =$f.text=
4. $f[^file::exec[cat^os[-windows].sh; ;args;un"quo ted";%PATH%;some\\ \r\n - enter?]]
   =$f.text=