[SQL] Typecast a user-defined type?

[Mark Volpe]

Hi,

I've created my own datatype for Postgres. I have found it necessary to be
able to convert it to text, so I could match it up with a text column in a
UNION. I figured Postgres would do this for me, but then, I'm naive. Can
someone give me a hint, or point me to the appropriate material on how to get
"value::text" to work with my new type?

Thanks,
Mark