Re: proposal: FOREACH-IN-ARRAY (probably for 9.2?)

On Fri, Dec 17, 2010 at 10:47 AM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Pavel Stehule <pavel(dot)stehule(at)gmail(dot)com> writes:
>> I am resending a redesigned proposal about special plpgsql statement
>> that support iteration over an array.
>
> OK ...
>
>> == Iteration over multidimensional arrays ==
>> Its designed to reduce one dimension from source array. It can remove
>> a slicing and simplify code:
>
> This seems like a really bad, confusing idea.  I think it should throw
> a type-mismatch error in this case.  If there is any use-case for such a
> thing, which I'm quite unconvinced of, it ought to use a separate syntax
> rather than overloading the element-by-element syntax.

I don't agree at all -- iterating arrays by slice is a frequently
requested feature (you can kinda sorta do it by slice notation, but
arr[n] giving null is a -general FAQ. This is how people think arrays
should work. I suppose that having this functionality reserved in a
tiny corner of plpgsql is not so good, but I think foreach... would
become the preferred way to iterate arrays always.

merlin