Module: JazzModel::ChordCollection

Defined in:
lib/jazz_model/chord_collection.rb

Overview

Intended to be used as a dynamic object extension of an Array representing a collection of chords for some added convenience.

For example, even though the base class is an Array, we can write:

  • scale.chords.symbols - For an array of symbols.

  • scale.chords.names - For an array of full names.

Instance Method Summary collapse

Instance Method Details

#names ⇒ Object

Returns array of chord names only



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# File 'lib/jazz_model/chord_collection.rb', line 26

def names
  self.map {|c| "#{c.key.name if c.key} #{c.name}".strip }
end

#resolve(symbol) ⇒ Object Also known as: []

WARNING: This is basically duplicated from Chord Try to make this DRY!

Resolves a chord symbol into a chord. Implementation is somewhat flakey due to the potential ambiguities arising from specifying key and symbols together.



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# File 'lib/jazz_model/chord_collection.rb', line 37

def resolve(symbol)
  in_key = nil

  return nil if symbol.nil?

  Key.all.each do |k|
    if symbol.starts_with?(k.name)
      in_key = k
      symbol.sub!(k.name, '').strip
      break
    end
  end

  chord_symbol = self.map {|c| c.symbols.to_a}.flatten.detect {|cs| cs.name == symbol}

  # Perhaps the matched key was really part of the name of the chord, try that:
  if chord_symbol.nil? && !in_key.nil?
    symbol = in_key.name + symbol
    chord_symbol = self.symbols[symbol]
  end

  # If still not found, must be invalid:
  return nil if chord_symbol.nil?

  chord = chord_symbol.chord
  chord.key = in_key unless in_key.nil?
  chord
end

#symbols ⇒ Object

Returns array of chord symbols only



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# File 'lib/jazz_model/chord_collection.rb', line 21

def symbols
  self.map {|c| "#{c.key.name if c.key}#{c.primary_symbol.name}" }
end

#to_s(format = :symbols) ⇒ Object

Formats chord collection



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# File 'lib/jazz_model/chord_collection.rb', line 13

def to_s(format = :symbols)
  case format
  when :symbols then symbols.join(', ')
  when :names then names.join(', ')
  end
end