User-Defined Types

Greetings.

During the development of a database often there is a need to change a
field's declaration from, say, VARCHAR(32) to, say, VARCHAR(64).

Having to go through and find all pertinent uses of VARCHAR(32) in the table
definitions (where it may be a foreign key) and in functions (where it may
be a parameter) to VARCHAR(64) is tedious and error prone.

Is there a simple way to make a user-defined type that is a specific
declaration of a built-in type (like VARCHAR(##)) without having to
implement the type's support functions?

Thanks,
David