[Python-Dev] transform() and untransform() methods, and the codec registry (original) (raw)

Victor Stinner victor.stinner at haypocalc.com
Fri Dec 3 17:44:17 CET 2010

On Friday 03 December 2010 16:11:29 R. David Murray wrote:

> >>> 'abc'.transform('hex') > TypeError: 'str' does not support the buffer interface > > >>> b'abc'.transform('rot13') > TypeError: expected an object with the buffer interface

I find these 'buffer interface' error messages to be the most confusing error message I get out of Python3 no matter what context they show up in. I have no idea what they are telling me. That issue is more general than transform/untransform, but perhaps it could be fixed for transform/untransform in particular.

If it's more general, let's open an issue for that: http://bugs.python.org/issue10616

> >>> b'abcd'.decode('hex') > TypeError: decoder did not return a str object (type=bytes) > > >>> 'abc'.encode('rot13') > TypeError: encoder did not return a bytes object (type=str)

These error messages make perfect sense to me. I think it is called "duck typing" :) (...) Please also recall that transform/untransform was discussed before the release of Python 3.0 and was approved at the time, but it just did not get implemented before the 3.0 release.

Ok.

Victor

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