f.nullable = false
	i := &c.p.Inst[f.i]
	i.Rune = r
	flags &= FoldCase // only relevant flag is FoldCase
	if len(r) != 1 || unicode.SimpleFold(r[0]) == r[0] {
		// and sometimes not even that
		flags &^= FoldCase
	}
	i.Arg = uint32(flags)
	f.out = makePatchList(f.i << 1)

	// Special cases for exec machine.
	switch {
	case flags&FoldCase == 0 && (len(r) == 1 || len(r) == 2 && r[0] == r[1]):
		i.Op = InstRune1

	if i.op() != InstRune || len(i.Rune) != 1 {
		return "", i.Op == InstMatch
	}

	// Have prefix; gather characters.
	var buf strings.Builder
	for i.op() == InstRune && len(i.Rune) == 1 && Flags(i.Arg)&FoldCase == 0 && i.Rune[0] != utf8.RuneError {
		buf.WriteRune(i.Rune[0])
		i = p.skipNop(i.Out)
	}
	return buf.String(), i.Op == InstMatch
}

// StartCond returns the leading empty-width conditions that must

            classes[it.simpleName] = c
        }
        [OldBase, OldSub, NewBase, NewSub].each {
            classes[it.simpleName] = instanceScopedPool.get(it.name)
        }

        classes['OldBase'].superclass = classes['OldSuperInternal']
        classes['NewBase'].superclass = classes['NewSuperInternal']
        classes['OldSub'].superclass = classes['OldBase']
        classes['NewSub'].superclass = classes['NewBase']

    static class OldSuper {}

    static class OldBase extends OldSuper {}

    static class NewSuper {}

    static class NewBase extends NewSuper {}

    @Incubating
    static class NewIncubatingBase extends NewSuper {}

    @Incubating
    interface IncubatingInterface {}

    interface InternalInterface {}

    interface StablePublicInterface {}

    CtClass oldBase
    CtClass newBase
    CtClass newSuper