Class: HeadMusic::Style::Guidelines::SingableIntervals

Inherits:
Annotation
  • Object
show all
Defined in:
lib/head_music/style/guidelines/singable_intervals.rb

Overview

A counterpoint guideline

Constant Summary collapse

PERMITTED_ASCENDING = 
%w[PU m2 M2 m3 M3 P4 P5 m6 P8].freeze
PERMITTED_DESCENDING = 
%w[PU m2 M2 m3 M3 P4 P5 P8].freeze
MESSAGE = 
"Use only PU, m2, M2, m3, M3, P4, P5, m6 (ascending), P8 in the melodic line."

Instance Method Summary collapse

Constructor Details

This class inherits a constructor from HeadMusic::Style::Annotation

Instance Method Details

#marks ⇒ Object 



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# File 'lib/head_music/style/guidelines/singable_intervals.rb', line 11

def marks
  melodic_note_pairs.reject { |note_pair| permitted?(note_pair) }.map do |pair_with_unpermitted_interval|
    HeadMusic::Style::Mark.for_all(pair_with_unpermitted_interval.notes)
  end
end

#permitted?(note_pair) ⇒ Boolean (private)

Returns:

  • (Boolean) 


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# File 'lib/head_music/style/guidelines/singable_intervals.rb', line 19

def permitted?(note_pair)
  melodic_interval = note_pair.melodic_interval
  whitelist_for_interval(melodic_interval).include?(melodic_interval.shorthand)
end

#whitelist_for_interval(melodic_interval) ⇒ Object (private) 



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# File 'lib/head_music/style/guidelines/singable_intervals.rb', line 24

def whitelist_for_interval(melodic_interval)
  melodic_interval.ascending? ? PERMITTED_ASCENDING : PERMITTED_DESCENDING
end