Como crear función en foxpro

Prueba así:

Messagebox(secreto("890"))

function secreto

lparameters lcnum as string

create cursor palabra(x n,letra c(1))

index on x tag x

insert into palabra(x,letra) values (1,"m")

insert into palabra(x,letra) values (2,"u")

insert into palabra(x,letra) values (3,"r")

insert into palabra(x,letra) values (4,"c")

insert into palabra(x,letra) values (5,"i")

insert into palabra(x,letra) values (6,"e")

insert into palabra(x,letra) values (7,"l")

insert into palabra(x,letra) values (8,"a")

insert into palabra(x,letra) values (9,"g")

insert into palabra(x,letra) values (0,"o")

lc=""

for z=1 to len(lcnum)

      seek(substr(lcnum,z,1))

      lc=lc+letra

endfor

return lc

Endfunc