So many threading primitives have different names on different platforms. This is basically Go's WaitGroup, except the C++ latch can't be incremented (it's otherwise identical). I wonder why that is?
/// ----------------------------------------------------------------------------
/// latches are great for multi-threaded tests with following sequence of steps
/// 1. setup test data
/// 2. create a latch
/// 3. create test threads each decrementing the latch-count
/// 4. when all threads have reached the latch, they are unblocked.
///
/// sligtly verbose commented code to illustrate this
void foo()
{
/// --------------------------------------------------------------------
/// create a latch with non-zero-count
unsigned const thread_count=...;
std::latch done(thread_count);
my_data data[thread_count];
std::vector<std::jthread> threads;
/// --------------------------------------------------------------------
/// threads decrement count as they are created
for(unsigned i=0;i<thread_count;++i)
threads.push_back(std::jthread([&,i]{
data[i]=make_data(i);
done.count_down();
do_more_stuff();
}));
/// --------------------------------------------------------------------
/// others wait for latch to be signalled, when the count reaches zero,
/// latch is permanently signalled, and threads are woken
done.wait();
process_data();
}
var wg sync.WaitGroup
wg.Add(1)
go func() {
defer wg.Done()
}()
wg.Wait()
...
wg.Add(1)
...
The phrasing is somewhat confusing: it is the waiting thread, not "they", that gets unblocked (count_down does not block).
EitherOwnedOrBorrowed and AtomicReferenceCountedPointer, but that'd be annoying to type once you know them.
and with most modern ide or even text editors providing autocompletion, (imho) i think abbreviations not really neccessary (though they can be fun in the case of kotlin ^^)
I too would love to know the specific reasoning though.
The C++ stdlib terminology is always so weird.
I still miss usint Ctrl-P when working with VS Code.