Can two functions call each other?

Question

I'm converting some code and have run into two functions that call each other. While I seem to have converted both functions to plsql ok, they do not compile, seemingly because they ref each other. As soon as I de-reference one one function's call to the other function they both compile.
I know that Oracle 10g supports recursion; and on the surface of things, this situation does not seem much different than recursion. If both functions are well formed, I would hope that they'd compile.
I wasn't able to find much by searching the forums on this topic...but I'm hoping that someone will have some info on this issue.

Answer 1

what happens when f2 sends 2 as parameter to f1 (i mean F1(2) in place of f1(1) ) at line 6 of f2).probably that what you expected ;) :
SQL>  create or replace function f1 (i integer default 0)
     return integer
as
begin
     dbms_output.put_line ('In function f1');
     return case when i != 1 then f2 end;
end f1;
Warning: compiled but with compilation errors
SQL>  show error
Errors for FUNCTION F1
LINE/COL ERROR                                                           
6/31     PLS-00201: identifier 'F2' must be declared                     
6/2      PL/SQL: Statement ignored                                       
SQL>  create or replace function f2
     return integer
as
     i integer;
begin
     dbms_output.put_line ('In function f2');
     execute immediate 'begin :1 := f1(2); end;' using out i;
     return i;
end f2;
Createfunction successfully completed.
SQL>  select f2() from dual
select f2() from dual
Error at line 1
ORA-00036: maximum number of recursive SQL levels (50) exceeded
ORA-06512: at "MICHAEL.F2", line 8
ORA-06512: at "MICHAEL.F1", line 6
ORA-06512: at line 1
ORA-06512: at "MICHAEL.F2", line 8
ORA-06512: at "MICHAEL.F1", line 6
ORA-06512: at line 1
ORA-06512: at "MICHAEL.F2", line 8
ORA-06512: at "MICHAEL.F1", line 6
ORA-06512: at line 1
ORA-06512: at "MICHAEL.F2", line 8
ORA-06512: at "MICHAEL.F1", line 6
ORA-06512: at line 1
ORA-06512: at "MICHAEL.F2", line 8
ORA-06512: at "MICHAEL.F1", line 6
ORA-06512: at line 1
ORA-06512: at "MICHAEL.F2", line 8
ORA-06512: at "MICHAEL.F1", line 6
ORA-06512: at line 1
ORA-06512: at "MICHAEL.F2", line 8
ORA-06512: at "MICHAEL.F1", line 6
ORA-06512: at line 1
ORA-06512: at "MICHAEL.F2", line 8
ORA-06512: at "MICHAEL.F1", line 6
ORA-06512: at line 1
ORA-06512: at "MICHAEL.F2", line 8
ORA-06512: at "MICHAEL.F1", line 6
ORA-06512: at line 1
ORA-06512: at "MICHAEL.F2", line 8
ORA-06512: at "MICHAEL.F1", line 6
ORA-06512: at line 1
ORA-06512: at "MICHAEL.F2", line 8