Combinatorial Operator Interleaver

oper.py

from itertools import product, permutations

"""
if __name__ == '__main__':
    for expr in generateOperators([2,3,4], ['+','-']):
        print(expr)
"""

def alternateBetween(items, operators):
    lenItems = len(items)
    lenOperators = len(operators)
    itemIter = 0
    opIter = 0
    isItem = True
    while True:
      if isItem and itemIter < lenItems:
          yield items[itemIter]
          itemIter += 1
      elif not isItem and opIter < lenOperators:
          yield operators[opIter]
          opIter += 1
      else:
          break
      isItem = not isItem

def generateOperators(iterable, operators):
  items = list(iterable)
  lenItems = len(items)
  for operatorMix in product(operators, repeat=lenItems-1):
        yield list(alternateBetween(items, operatorMix))