[Python-Dev] The -U flag

[Guido van Rossum]

> Since Python allows Unicode strings in sys.path, we are making
> progress on getting -U to work. When entering interactive mode, the
> stumbling block is
> 
> _idmap = ''
> for i in range(256): _idmap = _idmap + chr(i)
> del i
> 
> Here, _idmap is initialized with a Unicode string, and the chr(i)
> results are promoted to Unicode, which eventually causes a
> UnicodeErorr when you get past 127.
> 
> The work-around would be to write
> 
> _idmap = str('')
> for i in range(256): _idmap = _idmap + chr(i)
> del i
> 
> With that, we can enter interactive mode in python -U.
> 
> Is such a change acceptable?

Only with a comment that explains it -- otherwise the next person
looking at the code will remove it.

But didn't we at one point conclude that -U was never gonna work?  And
wasn't that why it's no longer documented?

--Guido van Rossum (home page: http://www.python.org/~guido/)