Read all the lines between a pattern match using Perl - regex

Question

I want to read a csv file. The csv files is like below,
cat,dog,0
apple,banana,0
#start_loop
jug,ball,0
tub, jar,3
#stop_loop
phone,bottle,10
#per head
#start_loop
cup,book,7
laptop,charger,9
#stop_loop
For above csv, I want to read between the #start and #stop. Also, I want to differentiate two #start_loop 's for ex, the lines from first #start_loop goes to one array and another #start_loop goes to another array.
The expected result would be:
#array1 = {jug ball 0, tub jar 3}
and
#array2 = { cup book 7, laptop charger 9}
How do I solve this problem?

Answer 1

You can use the flip-flop operator. It's value will be 1 for the #start line and will contain E for the #stop line.
#!/usr/bin/perl
use warnings;
use strict;
my #arr;
while (<>) {
chomp;
my $inside = /^#start_loop/ .. /^#stop_loop/;
if ($inside) {
push #arr, [] if 1 == $inside;
undef $inside if 1 == $inside
|| $inside =~ /E/;
push #{ $arr[-1] }, $_ if $inside;
}
}
use Data::Dumper; print Dumper \#arr;

Answer 2

Simplified version of choroba's solution:
my #arr;
while (<>) {
chomp;
my $inside = /^#start_loop/ .. /^#stop_loop/;
if ( $inside == 1 ) { push #arr, []; } # Start line
elsif ( $inside !~ /E/ ) { push #{ $arr[-1] }, $_; } # Middle line
}
Without the flip-flop:
my #arr;
my $inside;
while (<>) {
chomp;
if ( /^#start_loop/ ) { $inside = 1; push #arr, []; } # Start line
elsif ( /^#stop_loop/ ) { $inside = 0; } # Stop line
elsif ( $inside ) { push #{ $arr[-1] }, $_; } # Middle line
}