Indexing for Expression type data using GIST - Mailing list pgsql-hackers

Hi All,

I am trying to implement indexing mechanism for the Expression type data using GIST. For that purpose I need to store some extra information in the Meta-Data of the GIST Index.
The information is entered when the index is created on the table. Can any body give me some suggestion how to do that. I'll be really grateful.

Thanks in advance

Salman