for _, a := range attrs[i:] {
		if !a.Value.isEmptyGroup() {
			r.back = append(r.back, a)
		}
	}
}

// Add converts the args to Attrs as described in [Logger.Log],
// then appends the Attrs to the [Record]'s list of Attrs.
// It omits empty groups.
func (r *Record) Add(args ...any) {
	var a Attr
	for len(args) > 0 {
		a, args = argsToAttr(args)
		if a.Value.isEmptyGroup() {
			continue
		}

		for _, a := range as {
			if !a.Value.isEmptyGroup() {
				as2 = append(as2, a)
			}
		}
		as = as2
	}
	return Value{num: uint64(len(as)), any: groupptr(unsafe.SliceData(as))}
}

// countEmptyGroups returns the number of empty group values in its argument.
func countEmptyGroups(as []Attr) int {
	n := 0
	for _, a := range as {
		if a.Value.isEmptyGroup() {
			n++
		}
	}
	return n
}