[Q] $ARGV, <>, and command-line Perl

[John W. Krahn]

Interesting topic.

I have two follow up questions regarding this:

1. Is there a simple modification of this one-liner that would short
circuit the unnecessary reading of lines when $seen{$ARGV} evaluates
to true?

perl -ne'/whatever/&&print("$ARGV\n")&&close(ARGV)'

2. A related issue is the resetting of $. . Suppose that I wanted
to check for /whatever/ only within the first 10 lines of every
file.

perl -ne'(1..10)&&/whatever/&&print("$ARGV\n")&&close(ARGV);eof&&close(ARGV)'



John

 

[J Krugman]

As usual I've learned a huge deal from the responses I received to
my original post. With Perl I'm in a perpetual state of rank
newbiehood, even though I've been programming in it for years.

Many thanks,

jill

 

[chris-usenet]

By changing perl -ane to perl -alne you can eliminate the chomp and the
newlines from your code.

Ah. I had briefly wondered if that was possible, but hadn't even
considered the -l flag. Thanks for the heads up - it suddenly becomes
so much neater.

Chris