On Thursday, 5 December 2013 at 08:09:55 UTC, monarch_dodra wrote:
On Wednesday, 4 December 2013 at 23:14:48 UTC, Andrei
Alexandrescu wrote:
Hello,
Walter and I were talking about eliminating the surreptitious
allocations in buildPath:
http://dlang.org/phobos/std_path.html#.buildPath
We'd need to keep the existing version working, so we're
looking at adding one or more new overloads. We're looking at
giving the user the option to control any needed memory
allocation (or even arrange things such that there's no memory
allocated at all).
It's a generous design space, so although we have a couple of
ideas let's hear others first.
Thanks,
Andrei
Use an output range. It's the generic D approach, and what we
already do for the string functions such as
std.string.translate:
http://dlang.org/phobos/std_string.html#.translate
(look down for the output range overloads).
Anything "allocator" related should be carried by the output
range itself. The function itself should not care nor know
about any of that.
And thanks to your improvements[1] to put() output ranges should
actually be much more usable than they ever were before. I've
mentioned this a few times but I tried to add an output range
overload of toUpper and toLower but immediately encountered
problems with appending dchars to char arrays. Your recently
merged improvements to put() appear to have addressed that
problem and many others and I'll soon have another go at adding
these overloads now that that change is in place so thanks for
doing the hard work.
Before this got merged I don't even think output ranges could be
easily used for this improvement to buildPath so it got merged at
a very convenient time.
(my memory is a bit poor but if I'm remembering correctly
appender worked because it had done its own handling of narrow
strings but you couldn't just use a static or dynamic narrow
string array as an output range)
1. https://github.com/D-Programming-Language/phobos/pull/1569
