binary representation of an integer

Terry Reedy tjreedy at
Tue Jun 24 21:06:35 CEST 2008

cokofreedom at wrote:
> On Jun 24, 10:38 am, Mark Dickinson <dicki... at> wrote:

>> Interestingly, unlike hex and oct, bin doesn't add a trailing
>> 'L' for longs:
>>>>> bin(13L)
>> '0b1101'
>> I wonder whether this is a bug...

> Strange in 2.6, but I know at least in 3.0 that all integers are C
> Long's now, so the L is no longer required.

In current 2.x, the trailing L is no longer required for long integer 
input; the lexer decides whether to make an int or long.  Similarly, 
ints are automatically converted to longs as needed instead of raising 
overflow errors (as once happended).  The trailing L on output would 
have been removed already except for backward compatibility.  But there 
was no back-compatibility requirement for 0bxxxx strings.

In 3.0, all integers are class 'int'.  The internal representation as 
fixed or extended precision is entirely an internal implementation matter.

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