[Discuss-gnuradio] `next` branch: Now incorporating Python3

[Marcus Müller]

Dear Developer Community!

As you probably know, we've long had a `next` branch, in which the
"medium to long term" development happened – breaking changes are
allowed there, we experimented with Qt5 and a lot of other interesting
technologies.

Then, a really important change came upon us (more than that we chose
to have it): getting Python 3 compatibility became a necessity, as
multiple platform vendors announced they were planning on cutting out
Python2.

Thus, from `next` there was a separate `python3` branch; and from that,
many more feature and other development branches. We finally managed to
merge that back into `next`, hopefully to the fullest extent permitted
by ISO C++.

So, frankly, `next` now is *really* exciting. And if you got but a
spark of experience in your body, you know what /exciting/ means:
Yes, we could use some help spotting and fixing bugs.

We can build GNU Radio `next` on many machines (not all, Ubuntu seems
to break with Python3 somewhere in VOLK), we can /start/ GRC, but not
fully use it, and a lot of unit tests fail, because SWIG doesn't seem
to do the same magic with Python array-like objects for std::vectors,
and so on.

What will happen with next when we've fixed those?

Well, as soon as we can build everywhere we want (which is "in short,
the same systems as before, minus things as ancient as Ubuntu14.04,
plus Systems that only have Qt5 and Python3 instead of Qt4 and Py2")
and don't have regressions in our unit tests, we'll merge `next` into
`master`. Then, we'll have two weeks of "letting master proliferate in
the wild", and if that works out well, we'll focus on fixing the
outstanding `master` issues, and then will have a 3.8 release
candidate!

I'll address the state of the current `master` branch in a separate
mail.

Hope this does as much for a couple of people as much as it does for my
happiness :)

Best regards,
Marcus