[Python-Dev] bytes (original) (raw)

[Python-Dev] bytes / unicode

Guido van Rossum guido at python.org
Thu Jun 24 16:33:42 CEST 2010

On Thu, Jun 24, 2010 at 1:12 AM, Stephen J. Turnbull <stephen at xemacs.org> wrote:

Guido van Rossum writes:

 > For example: how we can make the suite of functions used for URL  > processing more polymorphic, so that each developer can choose for  > herself how URLs need to be treated in her application. While you have come down on the side of polymorphism (as opposed to separate functions), I'm a little nervous about it.  Specifically, Philip Eby expressed a desire for earlier type errors, while polymorphism seems to ensure that you'll need to Look Before You Leap to get early error detection.

Understood, but both the majority of str/bytes methods and several existing APIs (e.g. many in the os module, like os.listdir()) do it this way.

Also, IMO a polymorphic function should not accept mixed bytes/text input -- join('x', b'y') should be rejected. But join('x', 'y') -> 'x/y' and join(b'x', b'y') -> b'x/y' make sense to me.

So, actually, I don't understand what you mean by needing LBYL.

-- --Guido van Rossum (python.org/~guido)

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