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From: Random832 <random832@fastmail.com>
Newsgroups: comp.lang.python
Subject: Re: Mimick tac with python.
Date: Fri, 29 Jan 2016 23:58:38 -0500
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On Fri, Jan 29, 2016, at 23:46, Hongyi Zhao wrote:
> Hi all,
> 
> I can use the following methods for mimicking tac command bellow:
> 
> awk '{a[NR]=$0} END {while (NR) print a[NR--]}' input_file
> perl -e 'print reverse<>' input_file

Well, both of those read the whole file into memory - tac is sometimes
smarter than that, but that makes for a more complex program. And python
doesn't really do "one-liners" like that, so it doesn't look quite as
nice. But combined with some shell constructs you can do:

python <(echo 'import sys;print("".join(reversed(list(sys.stdin))))')