User blog comment:Googleaarex/Make an extension of the notation/@comment-5029411-20140926211035/@comment-25371339-20141001182744

a(-{(1)}-)-b = a(-&-)-b (first 1 level separator)

a(-{(2)}-)-b = a(-%-)-b

etc.

Replace {(1)} into {(-)}, {(2)} into {(--)}, etc

Then:

a(-{(-)(-)}-)-b = a(-{((-{((-{((-{(...(-{((-{((-{(-)}-)-)}-)-)}-)-...)}-)-)}-)-)}-)-)}-)-a with b levels (first 2 level separator)

a(-{(--)(-)}-)-b is next 1 level separator.

a(-{(-)(--)}-)-b is next 2 level separator.

a(-{(-)(-)(-)}-)-b is same as a(-{(-)(-)}-)-b, but with nests in the 2nd level (first level 3 separator)

etc.

Limit is a(-{(-)(-)(-)...(-)(-)(-)}-)-b