When a form is compiled, the PL/SQL compiler may encounter the name of an identifier that could be a procedure or function. The PL/SQL complier users a precedence mechanism to resolve ambiguities.
If an identifier such as PROCNAME is encountered that has the structure of a procedure or function, the compiler will use the first match found in the following search order:
If the answer is "no" to all of the above, then the compiler signals an error:
PL/SQL error 313 at line xxx, column yyy
'PROCNAME' not declared in this scope
or
PL/SQL error 201 at line xxx, column yyy
identifier 'FUNCTNAME' must be declared.