From: Robert Klemme <bob.news@...>
Date: 2004-10-05T17:29:51+09:00
Subject: Re: [yanq = yet another newbie question] correct syntax fovariable	and regexp


"Yvon Thoraval" <yvon.thoravalNO-SPAM@free.fr> schrieb im Newsbeitrag
news:1gl6f5h.1hzh8w1ct4lg5N%yvon.thoravalNO-SPAM@free.fr...
> Markus <markus@reality.com> wrote:
>
> > I am not sure exactly what you are asking, so I will offer multiple
> > suggestions and you can see what works best for you:
> Thanks for your answer, i need to clarify...
>
> I want, from a given file, output to a new file the lines containing a
> word (the example was "Bourgogne") given as the third arg of the script.
>
> Notice i'm able to do that in a "static" way that's to say changing the
> word in the script's regexp, what i don't know is the correct syntax to
> replace this word by a variable in the regexp, the variable being a
> String (ARGV[2].to_s).
> -- 
> yt

needle = ARGV[2]
rx = %r{^(.*)\s+#{needle}[\\s*|\\s+(.*)]}

If you want to be sure that meta symbols in needle are not interpreted you
can do this:

rx = %r{^(.*)\s+#{Regexp.escape needle}[\\s*|\\s+(.*)]}

What strikes me odd is the rest of your regexp, especially the square
brackets.  If you just want to match a certain word as word in the line
you should probably use these ones:

rx = %r{\b#{needle}\b}
rx = %r{\b#{Regexp.escape needle}\b}

"\b" matches a word boundary.

Kind regards

    robert