Python Gotcha's?

[Chris Angelico]

On Sun, Apr 15, 2012 at 8:47 AM, Bryan
<bryanjugglercryptographer at yahoo.com> wrote:
> Python 3(K) likes to use the same '.py' file extension as its
> incompatible predecessors, and in some/many/most *nix implementations,
> it likes to install in the same place. Python 3 is an improvement upon
> Python 2, but Python went from, "sure... Python just works," to,
> "well... that depends... which Python?"

But that's true of many things. (Is it still normal for web hosts to
offer PHP4 and PHP5?) The new version introduces something
incompatible, and some code breaks. Python has some excellent
facilities for managing this breakage (eg future imports), but it's
still always possible for somebody's script to break in an upgrade,
which is why package maintainers won't normally auto-upgrade you from
(say) 2.6.6 to 2.7.2, just in case. Python 3 is simply a larger body
of incompatible changes.

> I missed the 1 to 2 transition. I'm not exactly a Python newbie, but
> Python 1.5.2 was dead an buried by the time I met the snake^H^H^H^H^H
> group of daffy English k-ni-ghits.

Same here, but when I went poking around on one of my OS/2 servers, I
discovered a rather ancient Python - 1.5 or thereabouts - still
happily living there alongside the 2.6 or 2.7 that was the active
Python...

ChrisA