Re: Making a variable from a number in front of a string

I used a flag variable to tell me whether I'm inside the correct section. Also, using `(...)` in a regex creates a capture group, you can add 1 to it as to any other variable. Note that you need to backslash the parentheses to give them their literal meaning.

#!/usr/bin/perl
use warnings;
use strict;

my $printing;
my $next_section = q();
while (<DATA>) {
    if (/^\(([0-9]+)\) .*Significant Accounting Policies/) {
        $printing = 1;
        $next_section = 1 + $1;
    } elsif (/^\($next_section\)\s/) {
        undef $printing;
    }
    print if $printing;
}

__DATA__
(1) Preface

What is this all about.

(2) Summary of Significant Accounting Policies

Revenue Recognition

Revenue is recognized at the time goods are sold and shipped.

(3) Long-term Debt
[download]

($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,
[download]

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Re^2: Making a variable from a number in front of a string by porsche5k (Novice) on Jul 15, 2016 at 17:40 UTC
Thanks for the response. Here is a complete newbie question but what goes in "(<DATA>)?" Is that the file location?	[reply]
Re^3: Making a variable from a number in front of a string by Laurent_R (Canon) on Jul 15, 2016 at 17:53 UTC
The `<DATA>` file handle makes it possible to read the `__DATA__` section at the end of the program, i.e. in this case: `__DATA__ (1) Preface What is this all about. (2) Summary of Significant Accounting Policies Revenue Recognition Revenue is recognized at the time goods are sold and shipped. (3) Long-term Debt` [download] It simulates another file and it is a way to quickly test programs without having to create a separate test input file	[reply] [d/l] [select]
Re^4: Making a variable from a number in front of a string by Marshall (Canon) on Jul 15, 2016 at 18:22 UTC
The DATA file handle is actually even a bit cooler than that. To set this up, Perl opens the program for read and then seeks to the first byte after the __DATA__ line. Reading from DATA means that you are actually reading the program file. It is possible for the program to "read itself", i.e.: `#!/usr/bin/perl use warnings; use strict; ## DEMO of reading myself seek (DATA,0,0) or die "unable to seek $!"; print while <DATA>; __DATA__ some data would go here` [download] To re-read the DATA section, you could use a tell() to figure out where the initial DATA byte is and then later seek back to that initial byte offset.	[reply] [d/l]
Re^3: Making a variable from a number in front of a string by Marshall (Canon) on Jul 15, 2016 at 18:35 UTC
Maybe we didn't give you a crystal clear reply. First, the program should run using the data segment. Then take the data after __DATA__ and put that into "somefile". In the program, you need to add at the beginning, `open FILE, '<', "somefile" or die "unable to open file $!";` [download] Now put FILE everywhere that DATA appears in the program. You will now be reading "somefile" on the disk instead of the __DATA__ section.	[reply] [d/l]