This grammar implements a limited set of elements for parsing control tags.

e.g.

TAGS '<* *>'
TAGS ['<*', '*>']
TAGS = '<* *>'
TAGS = ['<*', '*>']
TAGS.inline '<* *>'
TAGS.inline = ['<*', '*>']
TAGS.* off
TAGS {
    inline = off
    outline => '...'
}