how to disallow a user from creating and modifying trigger but can creating and modifying stored procedure

Hi,

In sql 2005 (Enterprise edition if it makes any difference) I can't find a
permission combination that allows me to set up a user with following
intentions:
- Cannot modify anything other than create and modify store proc.
- Can execute all stored procs and functions.
- Can view all schema info about the database

Would anyone know how? Thanks!


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