blank lines representation in python

[Fredrik Lundh]

micklee74 at hotmail.com wrote:

> what is the correct way to represent blank lines in python (while
> iterating a file) without regexp? I know one way is to use
> re.search((line,r'^$') to grab a blank line, but i wanna try not to use
> regexp...
> is it
> 1) if line == ''": dosomething()  (this also means EOF right? )
> 2) if line is None: dosomething()
> 3) if not line: dosomething()
> thanks

    if line == "\n": # look for a single newline
        dosomething()

or

    if not line:
        ... end of file ...
    elif not line.strip(): # look for lines with nothing but whitespace
        dosomething()

</F>