Splits lists on separator elements with custom comparator function

chunk_on.py

def chunk_on(l, sep, test=lambda a, b: a == b, include_sep=False, skip_empty=True):
	'''for list `l`, yield slices that represent each run of the list between `sep`s.'''
	start = 0
	end = 0
	for i in range(len(l)):
		if test(l[i], sep):
			end = i
			if include_sep and i < len(l) - 1:
				end += 1
			if (skip_empty and start != end) or not skip_empty:
				yield l[start:end]
			start = end + 1
	if l[-1] != sep:
		yield l[start:]