string formatter %x and a class instance with __int__ or __long__cannot handle long

[Kenji Noguchi]

Hi

I'm using Python 2.4.4 on 32bit x86 Linux. I have a problem with printing
hex string for a value larger than 0x800000000 when the value is given to
% operator via an instance of a class with __int__(). If I pass a long value
to % operator it works just fine.

Example1 -- pass a long value directly. this works.

>>x=0x8000000 0
>>x

2147483648L

>>type(x)

<type 'long'>

>>"%08x" % x

'80000000'

Example2 -- pass an instance of a class with __int__()

>>class X:

.... def __init__(self, v):
.... self.v = v
.... def __int__(self):
.... return self.v
....

>>y = X(0x80000000)
>>"%08x" % y

Traceback (most recent call last):
File "<stdin>", line 1, in ?
TypeError: int argument required

>>>

The behavior looks inconsistent. By the way __int__ actually
returned a long type value in the Example2. The "%08x" allows
either int or long in the Example1, however it accepts int only
in the Example2. Is this a bug or expected?

by the way same thing happends on a 64bit system with a
value of 0x8000000000000 000.

Regards,
Kenji Noguchi

[half.italian@gmail.com]

Re: string formatter %x and a class instance with __int__ or __long__ cannot handle long

On Jun 20, 8:24 pm, "Kenji Noguchi" <tokyo...@gmail .comwrote:

Hi
>
I'm using Python 2.4.4 on 32bit x86 Linux. I have a problem with printing
hex string for a value larger than 0x800000000 when the value is given to
% operator via an instance of a class with __int__(). If I pass a long value
to % operator it works just fine.
>
Example1 -- pass a long value directly. this works.>>x=0x800 00000

>x

2147483648L

>type(x)

<type 'long'>

>"%08x" % x

>
'80000000'
>
Example2 -- pass an instance of a class with __int__()>>clas s X:
>
... def __init__(self, v):
... self.v = v
... def __int__(self):
... return self.v
...>>y = X(0x80000000)

>"%08x" % y

>
Traceback (most recent call last):
File "<stdin>", line 1, in ?
TypeError: int argument required
>
>
>
The behavior looks inconsistent. By the way __int__ actually
returned a long type value in the Example2. The "%08x" allows
either int or long in the Example1, however it accepts int only
in the Example2. Is this a bug or expected?
>
by the way same thing happends on a 64bit system with a
value of 0x8000000000000 000.
>
Regards,
Kenji Noguchi

In your second example y is an instance of class X...not an int. y.v
is an int. Are you hoping it will cast it to an int as needed using
your method? If so, I think you need to do so explicitly...ie "%08x"
% int(y)

~Sean