atomic_count.d

import core.atomic;

alias atomic_count = long;

void increment(ref shared atomic_count a, long b) {
    atomicOp!"+="(a, b);
}

unittest {
    import core.thread;

    shared atomic_count count = 0;

    void w() {
        for (int i = 0; i < 10_000; ++i) {
            increment(count, 1);
        }
    }

    void w2() {
        for (int i = 0; i < 10_000; ++i) {
            increment(count, 10_000);
        }
    }

    auto t1 = new Thread(&w);
    auto t2 = new Thread(&w2);
    
    t1.start();
    t2.start();

    t1.join();
    t2.join();

    assert(count == 100_010_000);
}