comment on

RegEx on multiple lines that might be large with look-ahead can really slow things down.

There is no need to hold onto chunks of anything - all you need is the PC name and you are fine up to when you see the next PC name.

The following chunk of code does that:


use strict   ;
use warnings ;


my @log_data = <DATA> ;

my $current_pc_name ;
foreach my $log_line ( @log_data ) { 
    chomp( $log_line );
    next unless( $log_line ) ;

    my ( $left, $right ) = split( /\:/, $log_line ) ;
    if( $left eq 'PCName' ) { 
    $current_pc_name = $right ;
    next ;
    } 

    unless( $current_pc_name ) { 
    die( "Command $log_line assigned to no PC!!" ) ;
    }

    print "PCName:$current_pc_name\n" ;
    print "$log_line\n\n"             ;

}





__DATA__
PCName: Foo1
Command1:dfie

Command2:dfo

Command3:dfum

PCName: Foo2

Command1:dfie

Command2:dfo

Command3:dfum
[download]

OUTPUT:

PCName: Foo1
Command1:dfie
PCName: Foo1
Command2:dfo
PCName: Foo1
Command3:dfum
PCName: Foo2
Command1:dfie
PCName: Foo2
Command2:dfo
PCName: Foo2
Command3:dfum
[download]

In reply to Re: File Find/Replace with the replacement coming from part of earlier matched string by tmharish
in thread File Find/Replace with the replacement coming from part of earlier matched string by navinc

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