pythonian way

[Fredrik Lundh]

Alexander Williams <thantos at chancel.org> wrote:
> >Yeah, but I need to remove empty lines as well...
>
> Try:
>
>    >>> A = filter(None, H.readlines())
>
> filter() with None as the function to use as the test for elements
> removes any that test as False intrinsically; since the empty line is
> always False, it returns a list with only strings with length.  Bingo.

not really.

readlines returns an empty line as "\n", not as
an empty string.  replacing None with a suitable
lambda expression might help:

    A = filter(lambda s: len(s) > 1, H.readlines())

or (easier to read), ignore empty lines (and maybe
comments too?) in the processing loop.  e.g.

    for line in H.readlines():
        if line[:1] in "#\n":
            continue # skip this one
        ...

</F>