Word counter script

Question

I made a word counter. It works as long as there aren't any lone punctuation marks. How could it be improved? (Could it be made simpler? Are the comments detailed/clear enough? etc.) I know it's simple, but I don't want to develop bad habits early on.

#prompt user to input a sentence
toCount = raw_input("--- ")

#function that counts words of inputted sentence
def countWords(theString):

    stringLength = len(theString)

    #index for each character in string
    counter1 = 0

    #stores word count
    accumulator = 0

    #go through each character in input text. if a character is a space
    #with no preceding spaces, add 1 to word count.
    while counter1 < stringLength:
        stringChar = theString[counter1]
        if stringChar == ' ' and counter1 > 0 and theString[counter1 - 1] != ' ':
            accumulator = accumulator + 1
            counter1 = counter1 + 1
        else:
            counter1 = counter1 + 1

    #if last character in input text is not a space, add 1 to word count
    if theString[counter1 - 1] != ' ':
        accumulator = accumulator + 1

    output = "You typed " + str(accumulator) + " words."

    return output

print countWords(toCount)

Answer 1

Here's one way to simplify it:

inp = raw_input("--- ")

print len(inp.split())

I'm not sure if you were unaware of this or if you were reinventing-the-wheel.

Before I go all out, maybe you could comment or leave an edit on your question letting us know if you meant to reinvent things here.

Answer 2

As Alex L points out, your approach could be significantly simplified. However, in terms of the actual code you've written, there are a few definite improvements you could make.

---

You can use += and smarter scoping to simplify your loop. This:

if stringChar == ' ' and counter1 > 0 and theString[counter1 - 1] != ' ':
    accumulator = accumulator + 1
    counter1 = counter1 + 1
else:
    counter1 = counter1 + 1

simplifies to:

if stringChar == ' ' and counter1 > 0 and theString[counter1 - 1] != ' ':
    accumulator += 1
counter1 += 1

As a rule, fewer lines of code is less potential for error.

---

More generally, it is not a good idea to use a while loop where a for loop could be used; the former is generally more error-prone. Compare:

index = 0
while index < len(things):
    item = things[index]
    ...
    index += 1

with:

for index in range(len(things)):
    item = things[index]
    ...

---

Better still, rather than manually using an index, iterate over the iterable directly:

for item in things:
    ...

In your case, as you want to look at pairs of consecutive items, you can use zip and a slice:

for first_item, second_item in zip(things, things[1:]):
    ...