Re: [Review] Re: minor patch submission: CREATE CAST ... AS EXPLICIT

On 2013-06-24 09:55:22 -0400, Tom Lane wrote:
> Andres Freund <andres@2ndquadrant.com> writes:
> > What about simply not using a keyword at that location at all? Something
> > like the attached hack?
> 
> "Hack" is much too polite a word for that.  This will for example fail
> to respect the difference between quoted and unquoted words.

Well. If you you have a better name for some quick proof of concept
patch...

Anyway: The point of the patch is not to suggest the use 'name' for that
- although we already do that in some places - but to prove that we can
get away with sort of "undeclared" keywords in a bunch of places. I
think doing so can reduce the number of keywords in a bunch of
places. E.g. EXPLICIT wouldn't need to be one if we invented
infrastructure for it.
The scanner obviously cannot discern those from real keywords and
literals, but we can easily do a recheck in code in the specific bison
rules as long as we are sure the syntax is unambigous. Which it is a in
a good part of the DDL support which in turn is a good sized part of the
overall grammar.

Greetings,

Andres Freund

-- Andres Freund                       http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training &
Services