Hi,
It looks we're creeping towards agreement in
http://archives.postgresql.org/message-id/20161206034955.bh33paeralxbtluv%40alap3.anarazel.de
It'd be fairly easy to add a hook in its ExecInstantiateExpr(), which'd
allow extensions to provide newer (presumably faster) ways to evaluate
expressions.
I myself have no use for this, I'm determined to get JITed expression
evaluation into core. But I could see others finding it useful.
Even if the concensus were that we want a hook there, I do not plan to
add it before this is committed, and a few other items are addressed.
But the discussion might take some time, so ...
- Andres