As a simple example, imagine a language of identity statements of the style

total=price+tax+shipping
         tax=price×10÷100
         shipping=5

expressed by this grammar that uses the definition of expr from another module:

+uses expr from expr.ixml
             data: identity+.
         identity: id, -"=", expr, -#a.
               id: [L]+.

The only problem is that the expr module has a clashing rule for id:

+shares expr
         expr: id++op.
           id: [L; Nd]+.
           op: ["+-×÷"].

Since the invoking grammar never gets changed, the rule in the module gets renamed, resulting in the following complete grammar:

data: identity+.
         identity: id, -"=", expr, -#a.
               id: [L]+.

             expr: id_++op.
           id_>id: [L; Nd]+.
               op: ["+-×÷"].

If the module's rule for id had instead been a renaming, it could have looked like this:

id>ident: [L; Nd]+.

and the renaming would have ended up as:

id_>ident: [L; Nd]+.