private static final class Digit extends RangesMatcher {
    // Plug the following UnicodeSet pattern into
    // https://unicode.org/cldr/utility/list-unicodeset.jsp
    // [[:Nd:]&[:nv=0:]&[\u0000-\uFFFF]]
    // and get the zeroes from there.

    // Must be in ascending order.
    private static final String ZEROES =

  private static final class Digit extends RangesMatcher {
    // Plug the following UnicodeSet pattern into
    // https://unicode.org/cldr/utility/list-unicodeset.jsp
    // [[:Nd:]&[:nv=0:]&[\u0000-\uFFFF]]
    // and get the zeroes from there.

    // Must be in ascending order.
    private static final String ZEROES =

		default:
			st.fail("unrecognized special G name code")
			panic("not reached")
		}
	}
}

// callOffset parses:
//
//	<call-offset> ::= h <nv-offset> _
//	              ::= v <v-offset> _
//
//	<nv-offset> ::= <(offset) number>
//
//	<v-offset> ::= <(offset) number> _ <(virtual offset) number>
//
// The c parameter, if not 0, is a character we just read which is the

// tail of buf, omitting trailing zeros. It omits the decimal
// point too when the fraction is 0. It returns the index where the
// output bytes begin and the value v/10**prec.
func fmtFrac(buf []byte, v uint64, prec int) (nw int, nv uint64) {
	// Omit trailing zeros up to and including decimal point.
	w := len(buf)
	print := false
	for i := 0; i < prec; i++ {
		digit := v % 10
		print = print || digit != 0
		if print {
			w--