make WWW_Find work again, now that its ML modules reside within a theory context (cf. bf5b45870110) -- patch by Rafal Kolanski;
package Greatest_Common_Divisor
is
--# function Gcd(A, B: Natural) return Natural;
procedure G_C_D(M, N: in Natural; G: out Natural);
--# derives G from M, N;
--# pre M >= 0 and N > 0;
--# post G = Gcd(M,N);
end Greatest_Common_Divisor;