On Mon, Jul 25, 2016 at 4:18 PM, Dima Pasechnik <dimp...@gmail.com> wrote: > > > On Monday, July 25, 2016 at 2:54:17 PM UTC+1, rjf wrote: >> >> I found this >> https://docs.python.org/3/howto/pyporting.html >> Which says that, in spite of various tools, you might have to rewrite code >> "manually". >> >> If you write code in Python 2.x and it has to be changed to run in Python >> 2.y and then >> again in Python 3, then that counts as a bad mark against Python, in my >> opinion.
> IMHO fully backward-compatible languages are a minority; e.g. Fortran and C > are not. > Maybe from the CL ivory tower things look differently, though. The difficulty of the Python 2 to Python 3 transition has been hashed out extensively in the Python community over the last many years. See http://python-notes.curiousefficiency.org/en/latest/python3/ as a starting point. The elevator summary is that one of the two main things they wanted to fix in Python 3 were to make print() a function, and to make strings unicode by default and clean up the text/bytes distinction. A few other warts too (like the <> operator). It was decided that since some backwards-compatibility breaking changes were made anyways (and projects like lib2to3 already underway to help automate transitioning), Python 3 would be *the* release to cram in as many backwards-incompatible changes that the community had been wanting to clean up for a long time anyways. The transition ended up being much more difficult than anyone expected. In particular the unicode/bytes changes created a great deal of difficulty for libraries dealing with low-level protocols. Through Python 3.3 several tweaks were made to make transitioning easier (such as reintroduction of the u'' syntax). Now it is quite routine to write code that supports Python 3 and 2 simultaneously. This kind of big upheaval won't happen again, or at least none is planned. There aren't any major issues anyone is chomping at the bit to fix that will introduce such massive backwards-incompatibility. Python 4 will just be the version after Python 3.9 ( https://opensource.com/life/14/9/why-python-4-wont-be-python-3 ) >> What is your opinion? What part of the culture am I missing? I'm not sure what William meant, but I think all you're missing is that for most of the rest of the Python community this is a dead horse. Best, Erik -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at https://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.