On 2008-05-19 17:14, Guido van Rossum wrote:
Hm, Martin is pretty convincing here. Before we go ahead and accept .transform() and friends (by whatever name) we should look for convincing use cases where the transformation is typically given by some other input, rather than hard-coded in the app. (And cases where there are two or three possibilities from a fixed menu don't count -- so that would rule out Content-transfer-encoding.)
The .transform() methods are meant as interface to same type codecs in general, not just compression algorithms. They are convenience methods to the codecs registry with the added benefit of applying type checks which the codecs registry does not guarantee since it only manages codecs. Of course, you can write everything directly against the codec registry or some other specialized interface, but that's not really what we're after here. The methods are meant to make code easy to write in the general use case, without having to worry about special parameters or finding the right module and function names. Motivation: When was the last time you used a gzip compression option (ie. yes there are options, but do you use them in the general use case) ? Can you write code that applies UU encoding without looking up the details in the documentation (ie. there is a module for doing UU-encoding in the stdlib, but what's it's name, what's the function, does it need extra logic) ? The motivation is not driven by having the need to pass a configuration parameter to a .transform() method. It's being able to write str.transform('gzip').transform('uu') which doesn't require knowledge about the modules doing the actual work behind the scenes. We're not adding those methods because there's no other way to get the functionality. It's all about usability, readability and PEP20 ("Beautiful is better than ugly."). -- Marc-Andre Lemburg eGenix.com Professional Python Services directly from the Source (#1, May 19 2008) >>> Python/Zope Consulting and Support ... http://www.egenix.com/ >>> mxODBC.Zope.Database.Adapter ... http://zope.egenix.com/ >>> mxODBC, mxDateTime, mxTextTools ... http://python.egenix.com/ ________________________________________________________________________ :::: Try mxODBC.Zope.DA for Windows,Linux,Solaris,MacOSX for free ! :::: eGenix.com Software, Skills and Services GmbH Pastor-Loeh-Str.48 D-40764 Langenfeld, Germany. CEO Dipl.-Math. Marc-Andre Lemburg Registered at Amtsgericht Duesseldorf: HRB 46611 _______________________________________________ Python-3000 mailing list Python-3000@python.org http://mail.python.org/mailman/listinfo/python-3000 Unsubscribe: http://mail.python.org/mailman/options/python-3000/archive%40mail-archive.com