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From: Ted Zlatanov <tzz@lifelogs.com>
To: help-gnu-emacs@gnu.org
Subject: Re: how to manipulate data like awk or perl when visiting a file
Date: Tue, 30 Dec 2008 08:57:48 -0600	[thread overview]
Message-ID: <86ocytaexf.fsf@lifelogs.com> (raw)
In-Reply-To: mailman.3532.1230620390.26697.help-gnu-emacs@gnu.org

On Tue, 30 Dec 2008 00:59:28 -0600 Harry Putnam <reader@newsguy.com> wrote: 

HP> I got pretty interested reading [Xah's] comparison of perl vs elisp. 

HP> What prompted my question here was that I had no access to shell tools
HP> or perl on a specific machine I was on right then, so it got me to
HP> thinking why I never see much mention of using elisp for those kinds
HP> of jobs.

HP> Its an interesting subject but in fact I'm rarely in that situation
HP> so usually rely on shell tools awk and perl.  Those I have some small
HP> grasp of.

The biggest problem with ELisp file processing vs. Perl/awk/etc. is that
efficient line-by-line processing is not possible.  Thus you're limited
to either byte offsets or what will fit in a buffer.  This is a big
inconvenience for large files.

Also, concise one-liners are trivial with Perl and awk, while Emacs
one-liners are painfully verbose (with the one saving grace that $
doesn't show up much in ELisp code).  By the time you're on the third
screen line, you've forgotten what you needed in the first place.

Ted


  parent reply	other threads:[~2008-12-30 14:57 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <mailman.3478.1230524085.26697.help-gnu-emacs@gnu.org>
2008-12-29  6:02 ` how to manipulate data like awk or perl when visiting a file rustom
2008-12-29  6:19   ` poppyer
2008-12-29  6:14 ` Xah Lee
2008-12-30  6:59   ` Harry Putnam
     [not found]   ` <mailman.3532.1230620390.26697.help-gnu-emacs@gnu.org>
2008-12-30 14:57     ` Ted Zlatanov [this message]
2008-12-29  4:14 reader
2008-12-30 14:34 ` Kevin Rodgers
     [not found] ` <mailman.3568.1230647701.26697.help-gnu-emacs@gnu.org>
2008-12-30 15:02   ` Richard Riley

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