File Coverage

blib/lib/Music/PitchNum/ASPN.pm

Criterion	Covered	Total	%
statement	25	25	100.0
branch	9	10	90.0
condition	2	2	100.0
subroutine	7	7	100.0
pod	2	2	100.0
total	45	46	97.8

# -*- Perl -*-
#
# Pitch number roles using the American Standard Pitch Notation (ASPN)
# format, or something probably close enough.
#
# Run perldoc(1) on this file for additional documentation.

package Music::PitchNum::ASPN;

use 5.010000;
use Moo::Role;
use POSIX qw/floor/;
use Scalar::Util qw/looks_like_number/;

our $VERSION = '0.09';

my %NOTE2NUM = (
  C => 0,
  D => 2,
  E => 4,
  F => 5,
  G => 7,
  A => 9,
  B => 11,
);

my %NUM2NOTE = (
  0  => 'C',
  1  => 'C#',
  2  => 'D',
  3  => 'D#',
  4  => 'E',
  5  => 'F',
  6  => 'F#',
  7  => 'G',
  8  => 'G#',
  9  => 'A',
  10 => 'A#',
  11 => 'B',
);

##############################################################################
#
# METHODS

sub pitchname {
  my ( $self, $number, %params ) = @_;
  die "need a number for pitchname\n" if !looks_like_number $number;

  $params{ignore_octave} //= 0;

  return $NUM2NOTE{ $number % 12 }
    . ( $params{ignore_octave} ? '' : ( floor( $number / 12 ) - 1 ) );
}

sub pitchnum {
  my ( $self, $name ) = @_;

  # already a pitch number, but nix the decimal foo
  return int $name if looks_like_number $name;

  my $pitchnum;

  # Only sharps, as the Young article only has those. Use the main
  # module for looser pitch name matching.
  if ( $name =~ m/ (?[A-G]) (?[#])? (?-?[0-9]{1,2}) /x ) {
    $pitchnum = 12 * ( $+{octave} + 1 ) + $NOTE2NUM{ $+{note} };
    $pitchnum++ if defined $+{chrome};
  }

  return $pitchnum;
}

1;
__END__