Your bracket notation in effect works the same as mine. The difference is that -+- could be any of [-+][--] or [--][+-] by symmetry and so leaving out brackets.

Your bracket notation in effect works the same as mine. The difference is that -+- could be any of [-+][--] or [--][+-] by symmetry and so leaving out brackets. In my notation "+" is a character which does not occupy space. Hence [-+][--][-+][--] is the same as -+--+-. Sorry about the error earlier: "...-+-+-" was a typo that I couldn't edit anymore.