initial start on PrefVote::KR2

src/perl/kr2/lib/PrefVote/KR2.pm

@@ -0,0 +1,43 @@
+# PrefVote::KR2
+# ABSTRACT: Kluft Rank-Rate (KR2) vote counting module for PrefVote
+# Copyright (c) 2023 by Ian Kluft
+# Open Source license: Apache License 2.0 https://www.apache.org/licenses/LICENSE-2.0
+
+# pragmas to silence some warnings from Perl::Critic
+## no critic (Modules::RequireExplicitPackage)
+# This solves a catch-22 where parts of Perl::Critic want both package and use-strict to be first
+use strict;
+use warnings;
+## use critic (Modules::RequireExplicitPackage)
+
+package PrefVote::KR2;
+
+use utf8;
+use autodie;
+use Data::Dumper;
+use Readonly;
+use Set::Tiny qw(set);
+
+# class definitions
+use Moo;
+use MooX::TypeTiny;
+use MooX::HandlesVia;
+use Types::Common         qw(Str ArrayRef HashRef InstanceOf PositiveOrZeroInt NonEmptySimpleStr);
+use PrefVote::Core::Float qw(fp_equal fp_cmp);
+use PrefVote::Core::Set   qw(Set);
+use PrefVote::Core::TestSpec;
+extends 'PrefVote::Core';
+
+# blackbox testing structure
+Readonly::Hash my %blackbox_spec => (
+    winners  => [qw(list set string)],
+    pair     => [qw(hash hash PrefVote::KR2::PairData)],
+);
+PrefVote::Core::TestSpec->register_blackbox_spec(
+    __PACKAGE__,
+    spec   => \%blackbox_spec,
+    parent => 'PrefVote::Core'
+);
+__PACKAGE__->ballot_input_ties_policy(1);    # set flag for Core: this class allows input ballots to set A/B ties
+
+# TODO to be continued...