Regular expression match in file

perlsen has asked for the wisdom of the Perl Monks concerning the following question:

Hi, Monks, i have the text file which contains various levels and their text.
I have to match the texts in the one level to next level that should be stored in the arrays.
Can u give some suggestions.

text file inputs:

level 1
section1
section2
level 2
section3
section4
level 2

output needed

@array[0]: level 1:  
section1
section2

@array[1]:  level 2:
section3
section4
[download]

Thanks in advance.

Comment on Regular expression match in file Download Code

Replies are listed 'Best First'.
Re: Regular expression match in file by gopalr (Priest) on Feb 11, 2005 at 06:29 UTC
Hi, Use Array Reference. `$file=' level 1 section1 section2 level 2 section3 section4 level 2 '; while ($file=~s#(level [0-9].+?)(level [0-9])#$2#s) { $a=$1; @b=$a=~m#(section[0-9])#g; push (@array, [@b]) }` [download]	[reply] [d/l]
Re: Regular expression match in file by holli (Abbot) on Feb 10, 2005 at 12:02 UTC
`use strict; use warnings; use Data::Dumper; my %levels = (); my $level = 0; while (<DATA>) { chomp; if (/^level (\d+)/) { $level = $1; } elsif (/^section(\d+)/) { push @{$levels{$level}}, $_; } } print Dumper (\%levels); __DATA__ level 1 section1 section2 level 2 section3 section4 level 2` [download] Output: `$VAR1 = { '1' => [ 'section1', 'section2' ], '2' => [ 'section3', 'section4' ] };` [download] holli, /regexed monk/	[reply] [d/l] [select]
Re: Regular expression match in file by cog (Parson) on Feb 10, 2005 at 11:45 UTC
`while (<>) { if (/^level (\d+)/) { $i = $1; } else { $array .= $_; } }` [download] Does that do the trick?	[reply] [d/l]
Re: Regular expression match in file by reneeb (Chaplain) on Feb 10, 2005 at 11:58 UTC
I would use the following code: `#! /usr/bin/perl use strict; use warnings; use Data::Dumper; my $file = './test.txt'; my @array; { local $/ = "\nlevel"; open(FILE,"<$file") or die $!; while(my $entry = <FILE>){ chomp $entry; $entry = 'level'.$entry unless($entry =~ /^level/); push(@array,$entry); } } print Dumper(\@array);` [download]	[reply] [d/l]


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