YAKUBU v ATTORNEY-GENERAL AND OTHERS     Constitutional law—Pension—Retiring awards of superior court justices—Right to pension equal to salary of serving justice of superior court—Article 155 conferring right on only retiring judges serving not less than ten continuous years as superior court justices or twenty years in public service inclusive of at least five continuous years as justice of superior court—Plaintiff serving less than ten continuous years as High Court judge—Total service  of plaintiff in public service 30 years but inclusive of only two and half years as substantive High Court judge—Four years and two months plaintiff acted as High Court judge ineligible for inclusion in period of service as High Court judge—Whether plaintiff entitled to pension under article 155 or only as public officer—Pensions Ordinance, Cap 30 (1951 Rev), Sched, reg 20—Constitution, 1992, art 155(1) (a) and (b).