Perl - Grep function regular expression Post: 302446728

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Top Forums Shell Programming and Scripting Perl - Grep function regular expression Post 302446728 by adelsin on Thursday 19th of August 2010 12:08:51 PM

08-19-2010

Registered User

Quote:

When the file has a line with just single open paranthesis, then you will get regex error ?! What is the big deal in this ?

It would exit the program at this point.

I ended up having to go with passing $_ to a scalar variable and then placing the scalar variable into an array.

Code:

foreach (@logs){
open READ, "<$_" or die $!;
@temp=<READ>;
close READ;
    foreach (@filter){
        my $alt=$_;
        print grep {/\Q$alt\E/i} @temp ;    
        }
}

Thank you all for your help.

Quote:

If you dont understand the basics, you will end up in confusions.

This is why I'm here. I was able to figure out the problem after I thought about what was happening for awhile and researched how the grep() function operated. And remembered about Quotemetas.

Just out of curiosity, when I do the following:

Code:

foreach (@logs){
open READ, "<$_" or die $!;
#@temp=<READ>;
        foreach (@filter){
        my $alt=$_;
        print grep {/\Q$alt\E/i} <READ>;    
        }
close READ; 
}

It seems not to go through the @filter array, but rather only the first value of it. Why would this be when trying to read directly from the file?

adelsin

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LEARN ABOUT NETBSD

getbuildlog

GETBUILDLOG(1)						      General Commands Manual						    GETBUILDLOG(1)

NAME

       getbuildlog - download build logs from Debian auto-builders

SYNOPSIS

       getbuildlog package [version-pattern] [architecture-pattern]

DESCRIPTION

       getbuildlog downloads build logs of package from Debian auto-builders. It downloads build logs of all versions and for all architectures if
       version-pattern and architecture-pattern are not specified or empty, otherwise only build logs whose  versions  match  version-pattern  and
       build  logs  whose  architectures  match  architecture-pattern will be downloaded. The version and architecture patterns are interpreted as
       extended regular expressions as described in grep(1).

       If version-pattern is "last" then only the logs for the most recent version of package found on buildd.debian.org will be downloaded.

       If version-pattern is "last-all" then the logs for the most recent version found on each build log index will be downloaded.

OPTIONS

       -h, --help
	      Show usage information and examples.

       -V, --version
	      Show version and copyright information.

EXAMPLES

       getbuildlog hello 2.2-1 amd64
	      Download amd64 build log for hello version 2.2-1.

       getbuildlog glibc "" mips.*
	      Download mips(el) build logs of all glibc versions.

       getbuildlog wesnoth .*bpo.*
	      Download all build logs of backported wesnoth versions.

AUTHOR

       Written by Frank S. Thomas <fst@debian.org>.

DEBIAN
								 Debian Utilities						    GETBUILDLOG(1)

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