Extra line in output when printing inside a loop

Question

I can\'t figure out why the code #1 returns an extra empty line while code #2 doesn\'t. Could somebody explain this? The difference is an extra comma at the end of the code

Answer 1

Iterating over files keeps the newlines from the file. So there's one newline from your print, and one from the string.

A good way to test file semantics is with StringIO. Take a look:

>>> from StringIO import StringIO
>>> x = StringIO("abc\ncde\n")
>>> for line in x: print repr(line)
... 
'abc\n'
'cde\n'

The comma suppresses the newline from the print, as Levon says, so that there's only the newline from the string.

I strip newlines from strings using s.rstrip('\n'). It gets rid of any trailing newlines in any modernish format (Unix, Windows, or old Mac OS). So you can do print "(%d) %s" % (i, text.rstrip('\n')) instead.