notes

x12 path walk

path is relative to Functional (ST) loop

Each segment in an IG should have a unique path

Given the current path, the next segment

For a x12 path,
	list of f, nil if not matched.  new path if matched
first match wins
from specific to general
hardcode paths for ISA/GS/ST

map[x12path][
	[
		func(seg) (newpath, error)
	]
]

match func:
	closure on
	seg id
	seg id, SEG01
	seg id, SEG01-1
	seg id, SEG02
	loop repeats, resets?

Another method to walk from x12path_start to x12path_end
	counting, errors
	requirement errors
	iterator on traversed nodes