How can one predict which objects will get invalidated when a index is dropped?

How can one predict which objects will get invalidated when a index is dropped?

Below is a simple testcase. Could not get this information  from dependency$ and the *_dependencies views.

Thx in advance.

 C:\>sqlplus "/ as sysdba"

SQL*Plus: Release 11.2.0.1.0 Production on Fri Jul 2 11:59:01 2010

Copyright (c) 1982, 2010, Oracle.  All rights reserved.

Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production
With the Partitioning, Oracle Label Security, OLAP, Data Mining,
Oracle Database Vault and Real Application Testing options

SQL> DROP USER METALINK CASCADE
  2  ;
DROP USER METALINK CASCADE
          *
ERROR at line 1:
ORA-01918: user 'METALINK' does not exist

SQL> CREATE USER METALINK IDENTIFIED BY METALINK