Re: [PATCH] Fix conversion for Decimal arguments in plpython functions - Mailing list pgsql-hackers

From Szymon Guz
Subject Re: [PATCH] Fix conversion for Decimal arguments in plpython functions
Date
Msg-id CAFjNrYuPEeNLAPbjiFq0mydupXQScC+=MzOXVpEE+5s8JUYb+w@mail.gmail.com
Whole thread
In response to Re: [PATCH] Fix conversion for Decimal arguments in plpython functions  (Claudio Freire <klaussfreire@gmail.com>)
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On 28 June 2013 22:29, Claudio Freire <klaussfreire@gmail.com> wrote:
On Fri, Jun 28, 2013 at 5:14 PM, Steve Singer <steve@ssinger.info> wrote:
> On 06/27/2013 05:04 AM, Szymon Guz wrote:
>>
>> On 27 June 2013 05:21, Steve Singer <steve@ssinger.info
>> <mailto:steve@ssinger.info>> wrote:
>>
>>     On 06/26/2013 04:47 PM, Szymon Guz wrote:
>>
>>
>>
>>
>>
>>
>> Hi Steve,
>> thanks for the changes.
>>
>> You're idea about common code for decimal and cdecimal is good, however
>> not good enough. I like the idea of common code for decimal and cdecimal.
>> But we need class name, not the value.
>>
>> I've changed the code from str(x) to x.__class__.__name__ so the function
>> prints class name (which is Decimal for both packages), not the value. We
>> need to have the class name check. The value is returned by the function and
>> is a couple of lines lower in the file.
>>
>> patch is attached.
>>
>
> I think the value is more important than the name, I want to the tests to
> make sure that the conversion is actually converting properly.  With your
> method of getting the class name without the module we can have both.
>
> The attached patch should print the value and the class name but not the
> module name.


Why not forego checking of the type, and instead check the interface?

plpy.info(x.as_tuple())

Should do.

>>> d  = decimal.Decimal((0,(3,1,4),-2))
>>> d.as_tuple()
DecimalTuple(sign=0, digits=(3, 1, 4), exponent=-2)
>>> d.as_tuple() == (0,(3,1,4),-2)
True
>>> d = decimal.Decimal("3.14")
>>> d.as_tuple()
DecimalTuple(sign=0, digits=(3, 1, 4), exponent=-2)
>>> d.as_tuple() == (0,(3,1,4),-2)
True
>>>

Yea, however decimal and cdecimal have different outputs:

For decimal:

! INFO:  DecimalTuple(sign=1, digits=(1, 0, 0), exponent=0)

for cdecimal:

! INFO:  DecimalTuple(sign=1, digits=(1, 0, 0), exponent=0L)

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