On Mar 16, 3:51 pm, Shane Geiger <[EMAIL PROTECTED]> wrote:
> lines = open('/tmp/foo.py',
> "r").read().splitlines()
>
>
> previous_line =
> ''
>
>
> for line in
> lines:
>
>
> if "foo" in
> line:
>
>
> print "found foo in the current line. The previous line is: "
> +
> previous_line
>
> previous_line =
> line
>
>
>
>
>
>
> Qilong Ren wrote:
> > Hi,all
>
> > I am new to this list. And I am glade I am here.
> > I have a question. I need to do some text processing. I need to read
> > from a file line by line. If some line is met with some condition, the
> > previous line needs some modification. How to get the info of the
> > previous line?
>
> > Thanks!
> > Qilong
>
> > ------------------------------------------------------------------------
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> --
> Shane Geiger
> IT Director
> National Council on Economic Education
> [EMAIL PROTECTED] | 402-438-8958 | http://www.ncee.net
>
> Leading the Campaign for Economic and Financial Literacy
>
> sgeiger.vcf
> 1KDownload- Hide quoted text -
>
> - Show quoted text -
If the list is not long, zip the lines together in pairs:
lines = """
test1
test2
foo
test3
test4
""".split("\n")
for prev,curr in zip(lines[:-1],lines[1:]):
if "foo" in curr:
break
else:
prev = "<not found>"
print "line before foo is:", prev
prints:
line before foo is: test2
-- Paul
--
http://mail.python.org/mailman/listinfo/python-list
