From: Robert Klemme <shortcutter@...>
Date: 2007-04-27T18:15:04+09:00
Subject: Re: Output A File w/ Line Numbers?

On 27.04.2007 08:39, John Joyce wrote:
> I'd like to read a file and output its contents (just to terminal is 
> fine for simplicity) with line numbers.
> Is there a Ruby library method that handles this like unix cat?
> Of course we can write a looping one-liner, but it seems to me this 
> function must already exist.

11:09:44 [~]: ruby -ne 'print $., " ",$_' foo.txt
1 aaa
2 bbbb
11:09:58 [~]: cat foo.txt
aaa
bbbb
11:10:01 [~]: cat -n foo.txt
      1  aaa
      2  bbbb
11:10:04 [~]:

If you want it more integrated in a script:

11:11:00 [~]: ruby -e 'ARGF.each {|line| print ARGF.lineno, " ", line}' 
foo.txt
1 aaa
2 bbbb
11:11:03 [~]:

This also works with arbitrary IO's.

Kind regards

	robert