Split function

from __future__ import division
import unittest

############ Split words
def SplitInnerLoop1(text):
    i = 0
    res = []
    while i < len(text):
        while i < len(text) and text[i] == " ":
            i += 1
        if i >= len(text):
            break
        word = ""
        while i < len(text) and text[i] != " ":
            word += text[i]
            i += 1
        res.append(word)
    return res






def SplitHelpperFunc(text):
    def collect(text, start_i, is_good_char):
        chars = ""
        while start_i < len(text) and is_good_char(text[start_i]):
            chars += text[start_i]
            start_i += 1
        return start_i, chars

    i = 0
    res = []
    while i < len(text):
        i, spaces = collect(text, i, lambda ch: ch == " ")
        if i >= len(text):
            break
        i, word = collect(text, i, lambda ch: ch != " ")
        res.append(word)
    return res



def SplitInnerLoop2(text):
    i = -1
    res = []
    while i < len(text) - 1:
        i += 1
        if text[i] == " ":
            continue
        word = ""
        while i < len(text) and text[i] != " ":
            word += text[i]
            i += 1
        res.append(word)
    return res







def SplitInnerLoop3(text):
    i = -1
    res = []
    while i < len(text) - 1:
        i += 1
        if text[i] != " ":
            word = ""
            while i < len(text) and text[i] != " ":
                word += text[i]
                i += 1
            res.append(word)
    return res








def SplitStateMachine(text):
    in_word = False
    word = ""
    res = []
    for ch in text:
        if ch == " ":
            if in_word:
                res.append(word)
                word = ""
            in_word = False
        else:
            word += ch
            in_word = True
    if in_word:
        res.append(word)
    return res




def SplitStateMachineSentinal(text):
    in_word = False
    word = ""
    res = []
    for ch in text + " ":
        if ch == " ":
            if in_word:
                res.append(word)
                word = ""
            in_word = False
        else:
            word += ch
            in_word = True
    return res






def SplitListEmpty(text):
    res = [""]
    for ch in text:
        if res[-1] and ch != " ":
                res[-1] = res[-1] + ch
        else:
            if ch == " ":
                ch = ""
            res.append(ch)
    return filter(lambda word: word, res)










def SplitInnerIter(text):
    res = []
    it = iter(text)
    for ch in it:
        if ch != " ":
            word = ch
            for ch in it:
                if ch == " ":
                    break
                word += ch
            res.append(word)
    return res








def SplitRecursive(text, prevWord=" "):
    if prevWord == " ":
        if not text:
            return []
        if text[0] == " ":
            return SplitRecursive(text[1:])
        return SplitRecursive(text[1:], text[0])
    if not text:
        return [prevWord]
    if text[0] == " ":
        return [prevWord] + SplitRecursive(text[1:])
    return SplitRecursive(text[1:], prevWord + text[0])








def SplitRecursive2Helper(text, prev_word=""):
    if not text:
        return [prev_word]
    if text[0] == " ":
        return [prev_word] + SplitRecursive2Helper(text[1:])
    return SplitRecursive2Helper(text[1:], prev_word + text[0])

SplitRecursive2 = lambda text: filter(lambda word: word, SplitRecursive2Helper(text))




class TestSplitWords(unittest.TestCase):
  def test_All(self):
      funcs = [SplitInnerLoop1, SplitHelpperFunc, SplitInnerLoop2,
               SplitInnerLoop3, SplitStateMachine, SplitStateMachineSentinal,
               SplitListEmpty,
               SplitInnerIter, SplitRecursive, SplitRecursive2]

      for f in funcs:
          self.do_func(f)

  def do_func(self, func):
      s = ""
      a = func(s)
      self.assertEqual([], a)
      s = "x"
      a = func(s)
      self.assertEqual(["x"], a)
      s = " x"
      a = func(s)
      self.assertEqual(["x"], a)
      s = "x "
      a = func(s)
      self.assertEqual(["x"], a)
      s = " x "
      a = func(s)
      self.assertEqual(["x"], a)
      s = "a b c"
      a = func(s)
      self.assertEqual(["a", "b", "c"], a)
      s = "a b  c"
      a = func(s)
      self.assertEqual(["a", "b", "c"], a)
      s = "azzzz bcccc  ctttttt"
      a = func(s)
      self.assertEqual(["azzzz", "bcccc", "ctttttt"], a)