On Friday, 11 September 2015 at 20:29:56 UTC, Vladimir Panteleev
wrote:
https://github.com/D-Programming-Language/phobos/pull/3631
Apparently it was decided at DConf 2015 to remove std.stream
and friends from Phobos. But these modules have been left
untouched (i.e. they're "stable") for a long time, and there's
a lot of D code using them. This decision seems to go in an
opposite direction to other recent decisions (i.e. that we stop
breaking code). Is everyone (incl. Walter AND Andrei) on board
with this?
Walter and Andrei publicly agreed at dconf that it should be
removed. As I understand it, it was removed from the
documentation with 2.068 (but not yet deprecated), and now it's
been deprecated. Now, that being said, I think 2.070 is too soon
to remove it, because at the rate of releases that Martin is
targeting, that's maybe 6 months as deprecated, which makes it
far too easy IMHO for code to go from working to not compiling
without any warnings in between for someone who's not updating
their compiler frequently. Normally, the deprecation cycle has
been approximately one year as deprecated but documented and
approximately one year as deprecated but undocumented (and then
the symbol would be removed), so code would continue to work
as-is for about 2 years once something has been deprecated, which
is about 4x longer than what std.stream is currently marked for.
Now, granted, std.stream has essentially been marked as scheduled
for deprecation for some time now (embarassingly long really), so
in theory, it's not heavily used, but it's also pretty clear
based on newsgroup posts and SO and whatnot that it _is_ being
used on some level in spite of the fact that it's documentation
says that it's going away.
So, I intend to open a PR to fix the targeted removal time
(probably this evening) so that it's not quite so quick, but
it'll still be a year at most, I think, given that it's been
marked as scheduled for deprecation for so long and is no longer
in the docs.
After that, as Martin points out, it should go in undead where
folks can continue to use it if they really want to. But I don't
think that code should simply stop compiling within a sixth month
period. I'm all for deprecating and removing stuff that we want
to get rid of and really don't like keeping it around long term,
but we need a deprecation cycle that gives folks time to fix
their code, and sadly, a note in the documentation really doesn't
seem to be enough of a warning.
- Jonathan M Davis
