In Python 2.6, bytes is str

Christian Heimes lists at cheimes.de
Tue Oct 7 13:10:51 CEST 2008


Bryan Olson wrote:
> 
> Python 3 has the 'bytes' type, which the string type I've long wanted in 
> various languages. Among other advantages, it is immutable, and 
> therefore bytes objects can be dict keys. There's a mutable version too, 
> called "bytearray".
> 
> In Python 2.6, the name 'bytes' is defined, and bound to str. The 2.6 
> assignment presents some pitfalls. Be aware.

[...]

> I'm thinking I should just avoid using 'bytes' in Python 2.6. If there's 
>  another Python release between 2.6 and 3.gold, I'd advocate removing 
> the pre-defined 'bytes', or maybe defining it as something else.

I guess you got the intention of the bytes alias wrong. It's partly my 
fault because I didn't document the bytes alias. We are well aware that 
the bytes alias in 2.6 isn't fully compatible with the bytes type in 
3.0. The bytes alias isn't MEANT to be compatible, too. :)

At first I wanted to backport the bytes type from 3.0 to 2.6. But it was 
too many work and the implications of yet another types were too 
complex. So I just added the alias in order to help people with writing 
forward compatible code like e.g. isinstance(egg, bytes).

Summa summarum the bytes alias serves was added for documentary purpose 
and to aid the 2to3 transition of code where 'str' is ambiguous.

Christian




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