Re: Sanding down some edge cases for PL/pgSQL reserved words

Pavel Stehule <pavel(dot)stehule(at)gmail(dot)com> writes:
> Is there some description of what keywords should be reserved? If I
> remember correctly, the scanner was changed more times, and maybe more
> reserved keywords are not necessary.

Per the comment in pl_scanner.c:

* We try to avoid reserving more keywords than we have to; but there's
* little point in not reserving a word if it's reserved in the core grammar.
* Currently, the following words are reserved here but not in the core:
* BEGIN BY DECLARE EXECUTE FOREACH IF LOOP STRICT WHILE

This patch gets rid of EXECUTE and STRICT, but the others are harder
to de-reserve. I think most of the rest are there because they can
follow a block or loop label, and the same comment observes

* (We still have to reserve initial keywords that might follow a block
* label, unfortunately, since the method used to determine if we are at
* start of statement doesn't recognize such cases.

regards, tom lane