Re: implement CAST(expr AS type FORMAT 'template') - Mailing list pgsql-hackers

On Fri, Jul 3, 2026 at 12:09 AM David G. Johnston
<david.g.johnston@gmail.com> wrote:
> I'm not sure how to make the design less problematic: format is optional, and for casts that need a format to succeed
theyprovide a default. 

But that's not how casts work today. some_date::text shares neither
code nor behavior with to_char(some_date, 'some_built_in_constant').
It's completely separate. We're not going to rethink the basic design
of casts for the sake of CAST(...FORMAT...).

--
Robert Haas
EDB: http://www.enterprisedb.com