OurString and hasNext and getNext

main.py

# 
# 
#  _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
# |_|_|_|_|_|_|_|_|_|_|_|_|_|_|_|_|_|_|
#      |   |     |             |
#     |H| |L|   |W|           |D|
#     |E| |O|   |O|           |!|
#     |L|       |R|
#               |L|
# 
# 1) var def
# 2) print
# 3) hasNext, getNext
#  
#
#
class OurString:
    def __init__(self, arr):
        self.__a = arr
        self.__it = iter(self)
        self.__peek = None
    def __iterator(self):
      i, j = 0, 0
      arr = self.__a
      n = len(arr)
      while i < n:
        if arr[i] is None:
          i += 1
          continue
        s = arr[i]
        if j == len(s):
          j = 0
          i += 1
          continue
        yield s[j]
        j += 1
    def __iter__(self):
      return self.__iterator()
    def __str__(self):
      # We can use the object as an iterable,
      # since we defined __iter__() to return
      # the iterator (generator above).
      return "".join([x for x in self])
    def hasNext(self):
      if self.__peek:
        return True
      try:
        self.__peek = next(self.__it)
      except StopIteration:
        return False
      return True      
    def getNext(self):
      # return next character, or None
      c = None
      if self.hasNext():
        c = self.__peek
        self.__peek = None
      return c
    
s1 = OurString([None, None, "HEL", "LO", None, None, None, "WORL", None, "D!"])

# print() uses str() under the hood,
# which uses the __str__() method.
print(s1)

s2 = OurString([None, "Hi", None, None, "There!"])

while s2.hasNext():
  print(s2.getNext())

# Demo use of OurString as an iterable.
for c in s2:
  print(c, end="")
print("")