Re: Is there a better/simpler way to filter blank lines?

On Nov 4, 3:30 pm, tmallen <thomasmal...@xxxxxxxxx> wrote:
On Nov 4, 4:30 pm, bearophileH...@xxxxxxxxx wrote:

tmallen:

I'm parsing some text files, and I want to strip blank lines in the
process. Is there a simpler way to do this than what I have here?
lines = filter(lambda line: len(line.strip()) > 0, lines)

xlines = (line for line in open(filename) if line.strip())

Bye,
bearophile

I must be missing something:

xlines = (line for line in open("new.data") if line.strip())
xlines

<generator object at 0x6b648>>>> xlines.sort()

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'generator' object has no attribute 'sort'

What do you think?

Thomas

Using the surrounding parentheses creates a generator object, whereas
using square brackets would create a list. So, if you want to run list
operations on the resulting object, you'll want to use the list
comprehension instead.

i.e.

list_o_lines = [line for line in open(filename) if line.strip()]

Downside is the increased memory usage and processing time as you dump
the entire file into memory, whereas if you plan to do a "for line in
xlines:" operation, it would be faster to use the generator.
.

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