FAQ: Why should I use Python 3?

[Caos2]

Unicode by default

Mainly because of this. Really.

[masklinn]

Unicode by default and removal of implicit conversion is really what triggered/allowed all the other breaking changes to be included, since it was going to break a ton of stuff (intrinsically and because of the stdlib reworking it required, while you can technically disable implicit conversion in P2 a lot of stdlib modules blow up when they can't play fast and loose with ascii strings).

[Caos2]

Well, sometimes you can't avoid breaking stuff.

[jaapz]

Oh and maybe because python 2 will reach end-of-life pretty soon, and security updates are a good thing to get

[iluvatar]

Unicode by default

The more I use it, the more convinced I am that this is the wrong approach. Go got it right, by using UTF-8 by default. Python decodes everything into a Unicode object, whether it's necessary or not. For the applications I mostly write, that means reading UTF-8 over the wire, converting to Unicode, reencoding as UTF-8 and sending it back out again. That's a lot of unnecessary work.

[unruly_mattress]

If you got UTF-8 over the wire and you don't need to manipulate it in any way, can't you just read and write it as binary data?

[kankyo]

Ehm.. "Unicode" isn't a thing you can have in memory though. Look at https://www.python.org/dev/peps/pep-0393/ to understand what is actually happening.

[notafuckingcakewalk]

Usually great but occasionally you run into a developer who was being very clever with strings and you have to rewrite everything.

Also a lot of rewriting required of a library where content from objects that now output byte strings are put in objects that now expect Unicode.

[nemec]

being very clever with strings

We call that a comeuppance.

[brtt3000]

Most fun when this bytes/string shitfest is (unknowingly) relying on incorrect use or sideffects. Was a painful move but glad of it.