Existing law
Section 315(4) · 1999 Constitution (2004 edition)
What Constitution says
(4) In this section, the following expressions have the meanings assigned to them, respectively - (a) "appropriate authority" means - (i) the President, in relation to the provisions of any law of the Federation, (ii) the Governor of a State, in relation to the provisions of any existing law deemed to be a Law made by the House of Assembly of that State, or (iii) any person appointed by any law to revise or rewrite the laws of the Federation or of a State; (b) "existing law" means any law and includes any rule of law or any enactment or instrument whatsoever which is in force immediately before the date when this section comes into force or which having been passed or made before that date comes into force after that date; and (c) "modification" includes addition, alteration, omission or repeal.
This is the 1999 Constitution as published in 2004. Later amendments aren't included yet, so a section may have changed since.
Original source
Official Gazette · CFRN 1999 official PDF · printed page 128–129. Original document
Release: draft-c8d50d87fae9. Source scope, review and corrections