Why can't I call read() twice on an open file?

Question

For an exercise I\'m doing, I\'m trying to read the contents of a given file twice using the read() method. Strangely, when I call it the second time, it doesn\

Answer 1

Everyone who has answered this question so far is absolutely right - read() moves through the file, so after you've called it, you can't call it again.

What I'll add is that in your particular case, you don't need to seek back to the start or reopen the file, you can just store the text that you've read in a local variable, and use it twice, or as many times as you like, in your program:

f = f.open()
text = f.read() # read the file into a local variable
# get the year
match = re.search(r'Popularity in (\d+)', text)
if match:
  print match.group(1)
# get all the names
matches = re.findall(r'(\d+)(\w+)(\w+)', text)
if matches:
  # matches will now not always be None