[Python-Dev] Deprecating "U" open mode

Serhiy Storchaka storchaka at gmail.com
Fri Sep 28 23:48:54 CEST 2012

Since Python 2.3 many open-like functions supports "Universal line mode" 
(PEP 278 [1]). Since 3.0 (and 2.6) PEP 3116 [2] suggests better 
alternative -- io.TextWrapper.

In issue15204 [3] proposed to deprecate "U" mode in open-like functions. 
In fact I found only three places where "U" mode is mentioned in the 
standard library:

* builtin open (io.open) (almost ignored);
* fileinput (transparently passed to open);
* zipfile (inefficient and inconsistent implementation).

Is someone uses "U" mode and has objections?

[1] http://www.python.org/dev/peps/pep-0278/
[2] http://www.python.org/dev/peps/pep-3116/
[3] http://bugs.python.org/issue15204

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