Re: Function sugnature with default parameter

2014-02-26 20:36 GMT+01:00 Andrew Dunstan <andrew(at)dunslane(dot)net>:

>
> On 02/26/2014 01:51 PM, Josh Berkus wrote:
>
>> On 02/26/2014 10:15 AM, salah jubeh wrote:
>>
>>> I think, there is a difference between optional parameters and default
>>> parameter values. So, my suggestion would be something like this.
>>> SELECT default_test(1,3, DEFAULT); -- match function number 1
>>>
>>> SELECT default_test(1,3); -- match the function number 2
>>>
>>> SELECT default_test(1); -- ERROR
>>> Regards
>>>
>> This would break at least 4 major applications which I personally have
>> worked on, and the benefit to users is unclear at best.
>>
>> One of the main reasons to *have* default parameters is to allow adding
>> new parameters to existing functions without breaking old application
>> code. So, -1 from me.
>>
>>
> me too.
>
> The OP's statement that there is a difference between default params and
> optional params doesn't compute. The only way params are optional is that
> they have a default. Treating these as somehow independent is a nonsense.
>
> Furthermore, if we dropped function 2, then
>
> select default_test(1,3)
>
> would be a call to function 1. Then, if we followed this proposal,
> creating function 2 would magically steer that call to function 2 instead.
> Talk about a footgun, and possibly a security risk too.
>
>
more overloaded functions with similar type signature is just dangerous and
bad practice.

We would to disallow it.

Regards

Pavel

>
> cheers
>
> andrew
>
>
>
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