type aliases - Mailing list pgsql-general

I can create an alias of a type like:

CREATE DOMAIN myvarchar varchar;

But I can't declare a myvarchar with a variable size, eg "mycolumn myvarchar(42)" and from what I've read this is the
wayit DOMAIN is supposed to work so I can't do it that way. 

Is there a way to define myvarchar the way I want to? Can I use CREATE TYPE and just mirror the declaration of the
underlyingtype? 

Thanks

James