AoC 2023, day 19, part 1 (Perl)

#!/usr/bin/perl

use strict;
use warnings;

use feature         qw(say);
use List::Util      qw(sum);

# Paragraph mode, array of sections
$/ = '';
my @section = map {[split /\n/]} <>;

my %Rules;

foreach ($section[0]->@*) {
    my ($flow, $str) = m#(\w+)\{(.*)\}#g;

    my @rules;
    foreach my $rule (split( /,/, $str )) {
        if ($rule =~ m#([xmas])([<>])(\d+):(\w+)#) {
            push( @rules, "\$item{$1} $2 $3 and '$4'" );
        } else {
            push( @rules, "'$rule'" );
        }
    }

    $Rules{$flow} = \@rules;
}

my $part1 = 0;
foreach ($section[1]->@*) {
    my %item = map { split /=/ } m#([xmas]=\d+)#g;
    my $flow = 'in';

    FLOW:
    while ($flow ne 'A' and $flow ne 'R') {
        foreach my $rule ($Rules{$flow}->@*) {
            my $result = eval( $rule ) // '';
            if ($result) {
                $flow = $result;
                next FLOW;
            }
        }
    }

    $part1 += sum values %item  if ($flow eq 'A');
}

say "Part 1: $part1";