In order to give access to the procedure so that the other user can make changes is to .The SYS user should give him ALTER ANY PROCEDURE system privelege.And u as a user should give him EXECUTE PRIVELEGE on the procedure.
If the procedure contains undelying tables in ur schema,then u should also grant him necessaty privliges on the tables to that user.
Say a procedure proc1 is in SCOTT schema.And u want to give him access to make changes to the procedure as well as run that procedure to user A
Step 1)Connect as sys and
grant alter any procedure to A;
Step2)Connect as user SCOTT and
grant execute on proc1 to A;
if the procedure is accessing some tables in SCOTT schema,u have to grant the necessary priveleges on the underlying tables to user A also,
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