Tuplet Formatter-Navigating in the Program Reference

[Mehmet Okonsar]

To learn about formatting tuplets, I get into:
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tupletNumberFormatFunction (procedure)
Function taking a music as input, producing a string. This function is
called to determine the text to print on a tuplet bracket.
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Then how can I learn what are the options and their syntax, for example:
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\set tupletNumberFormatFunction = #fraction-tuplet-formatter
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what are the other options and what are their syntax? Where are they in the
Program reference?

Best Regards,
Mehmet Okonsar, pianist-composer
www.okonsar.com