Re: syntax question

On Thu, Jun  3, 2021 at 03:21:15PM -0400, Tom Lane wrote:
> Adrian Klaver <adrian.klaver@aklaver.com> writes:
> > On 6/3/21 12:01 PM, Bruce Momjian wrote:
> >> On Thu, Jun  3, 2021 at 08:58:03PM +0200, Marc Millas wrote:
> >>> within a function, I want to create another function.
> 
> >> You can't create functions inside of functions;  same for procedures.
> 
> > Sure you can:
> 
> Yeah.  The actual problem here is that Marc is expecting variable
> substitution to occur within a utility (DDL) statement, which it
> doesn't.  The workaround is to build the command as a string and
> use EXECUTE, as Adrian illustrated:
> 
> > EXECUTE  'create function ' ||  bidule || '() RETURNS void language 
> > plpgsql AS $fnc$ BEGIN END; $fnc$ ';
> 
> This is not terribly well explained in the existing docs.  I tried
> to improve the explanation awhile ago in HEAD:
> 
> https://www.postgresql.org/docs/devel/plpgsql-statements.html#PLPGSQL-STATEMENTS-GENERAL-SQL

Oh, I thought he wanted to declare a function inside the function that
could be called only by that function, like private functions in Oracle
packages can do.  Yes, you can create a function that defines a function
that can be called later.  I guess you could also create a function that
_conditionally_ creates a function that it can call itself too.  My
point is that you can't create a function that has function scope ---
they all have schema scope.

-- 
  Bruce Momjian  <bruce@momjian.us>        https://momjian.us
  EDB                                      https://enterprisedb.com

  If only the physical world exists, free will is an illusion.