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From: evans@decvax.DEC.COM (Marc Evans)
Newsgroups: comp.lang.perl
Subject: Re: I'm lazy, can this be done somehow???
Message-ID: <528@decvax.decvax.dec.com.UUCP>
Date: 29 Jan 91 14:29:44 GMT
References: <1991Jan26.012646.4937@sdd.hp.com>
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Reply-To: evans@decvax.DEC.COM
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Organization: Synergytics
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In article <1991Jan26.012646.4937@sdd.hp.com>, harless@sdd.hp.com (Mike Harless) writes:
|> 
|> 
|> What I'd like to do is suck up a file into an array, 
|> read another file to see how many lines I've already read (if any),
|> and then grep strings out of what's new.  The file of lines may have been 
|> zero'd out since the last time I read it, so I can't just start
|> reading after skipping so many lines.
|> 
|> For example, if I've read a file into the array @lines, and then found
|> out that I've already looked at the first 400 lines last time I ran, I'd 
|> like to do something like:
|> 
|> 	$[ = 400 ;
|> 	@found = grep(/whatever/, @lines) ;
|> 
|> and only have grep work on the lines after the first 400.  I know that
|> I could do this by using an index into @lines, but was trying to do
|> things elegantly.  I've heard rumors that using indices into arrays isn't 
|> the perl way! :-)  Is there something simple that I missed?

Shouldn't you be able to do this using the range construct, as in:

	@found = grep(/whatever/,$lines[400 .. $#lines]);

- Marc
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Marc Evans - WB1GRH - evans@decvax.DEC.COM  | Synergytics     (603)635-8876
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