(parser location fretboard-table chord tuning diagram-definition)
(hash-table? ly:music? pair? string-or-pair?)
(_i "Add predefined fret diagram defined by @var{diagram-definition}
(parser location fretboard-table chord tuning diagram-definition)
(hash-table? ly:music? pair? string-or-pair?)
(_i "Add predefined fret diagram defined by @var{diagram-definition}