How can I parse multiline records in Perl? - perl

Question

I'm trying to parse the string that use delimiter '#'
this string has 3 lines
101#Introduction to the Professor#SG_FEEL#QUE_NOIMAGE#
head up to the Great Hall and speak to the professor to check in for class.#
#
102#Looking for Instructors#SG_FEEL#QUE_NOIMAGE#
Look for the Battle Instructor.#
Talk to Battle Instructor#
103#Battle Instructor#SG_FEEL#QUE_NOIMAGE#
You have spoken to the Battle Instructor#
#
how to get each value before delimiter '#' so I can make a new format that look like this
[101] = {
Title = "Introduction to the Professor",
Description = {
"head up to the Great Hall and speak to the professor to check in for class."
},
Summary = ""
},
[102] = {
Title = "Looking for Instructors",
Description = {
"Look for the Battle Instructor."
},
Summary = "Talk to Battle Instructor"
},
[103] = {
Title = "Battle Instructor",
Description = {
"You have spoken to the Battle Instructor"
},
Summary = ""
},
Also there will be multiple data from 101 - n
I'm trying to use split with the code below:
#!/usr/bin/perl
use strict;
use warnings;
my $data = '101#Introduction to the Professor#SG_FEEL#QUE_NOIMAGE#';
my #values = split('#', $data);
foreach my $val (#values) {
print "$val\n";
}
exit 0;
and the output:
101
Introduction to the Professor
SG_FEEL
QUE_NOIMAGE
How to read multiple line data? And also how to exclude some data, for example to match the new format, I don't need SG_FEEL and QUE_NOIMAGE data

Answer 1

The Perl special variable $/ sets the "input record separator"—the string that Perl uses to decide where a line ends. You can set that to something else.
use v5.26;
use utf8;
use strict;
use warnings;
$/ = "\n\n"; # set the input record separator
while( <DATA> ) {
chomp;
say "$. ------\n", $_;
}
__END__
101#Introduction to the Professor#SG_FEEL#QUE_NOIMAGE#
head up to the Great Hall and speak to the professor to check in for class.#
#
102#Looking for Instructors#SG_FEEL#QUE_NOIMAGE#
Look for the Battle Instructor.#
Talk to Battle Instructor#
103#Battle Instructor#SG_FEEL#QUE_NOIMAGE#
You have spoken to the Battle Instructor#
#
The output shows that you read whole records with each call to <DATA>:
1 ------
101#Introduction to the Professor#SG_FEEL#QUE_NOIMAGE#
head up to the Great Hall and speak to the professor to check in for class.#
#
2 ------
102#Looking for Instructors#SG_FEEL#QUE_NOIMAGE#
Look for the Battle Instructor.#
Talk to Battle Instructor#
3 ------
103#Battle Instructor#SG_FEEL#QUE_NOIMAGE#
You have spoken to the Battle Instructor#
#
From there you can parse that record however you need.

Answer 2

Reading multiple lines is easy, see readline:
open my $fh, '<', $filename
or die "Couldn't read '$filename': $!";
my #input = <$fh>;
Now you want to go through all lines and look at what to do with them:
my $linenumber;
my %info; # We want to collect information
while ($linenumber < $#input) {
Each line that starts with nnn# starts a new item:
if( $input[ $linenumber ] =~ /^(\d+)#/ ) {
my #data = split /#/, $input[ $linenumber ];
$info{ number } = $data[0];
$info{ Title } = $data[1];
$linenumber++;
};
Now, read stuff into the description until we encounter an empty line:
while ($input[$linenumber] !~ /^#$/) {
$info{ Description } .= $input[$linenumber];
$linenumber++;
};
$linenumber++; # skip the last "#" line
Now, output the stuff in %info, formatting left as an exercise. I've used qq{} for demonstration purposes. You will want to change that to qq():
print qq{Number: "$info{ number }"\n};
print qq{Title: "$info{ Title }"\n};
print qq(Description: {"$info{ Description }"}\n);
};