Re: pl/pgsql feature request: shorthand for argument and local variable references

On Thu, Mar 18, 2021 at 3:45 PM Pavel Stehule <pavel(dot)stehule(at)gmail(dot)com> wrote:
>
>
>
> čt 18. 3. 2021 v 15:19 odesílatel Hannu Krosing <hannuk(at)google(dot)com> napsal:
...
>> Variation could be
>>
>> DECLARE
>> fnarg ALIAS FOR FUNCTION a_function_with_an_inconveniently_long_name;
>>
>> so it is clear that we are aliasing current function name
>>
>>
>> or even make the function name optional, as there can only be one, so
>>
>> DECLARE
>> fnarg ALIAS FOR FUNCTION;
>
>
> Why you think so it is better than just
>
> #routine_label fnarg
>
> ?

It just adds already a *third* way to (re)name things, in addition to
<< blocklabel >>
and ALIAS FOR

For some reason it feels to me similar to having completely different
syntax rules
for function names, argument names and variable names instead of all having to
follow rules for "identifiers"

For cleanness/orthogonality I would also prefer the blocklables to be in DECLARE
for each block, but this train has already left :)
Though we probably could add alternative syntax ALIAS FOR BLOCK ?

> Maybe the name of the option can be routine_alias? Is it better for you?

I dont think the name itself is bad, as it is supposed to be used for
both FUNCTION
and PROCEDURE renaming

> My objection to DECLARE is freedom of this clause. It can be used everywhere.
> the effect of DECLARE is block limited. So theoretically somebody can write
>
> BEGIN
> ..
> DECLARE fnarg ALIAS FOR FUNCTION;
> BEGIN
> ..
> END;
>
> END;
>
> It disallows simple implementation.

We could limit ALIAS FOR FUNCTION to outermost block only, and revisit
this later
if there are loud complaints (which I don't think there will be :) )

Cheers
Hannu