Method send

flow/include/flow/ThreadHelper.actor.h:527–555

	void delref() override { ThreadSafeReferenceCounted<ThreadSingleAssignmentVar<T>>::delref(); }

	void send(const T& value) {
		if (TRACE_SAMPLE())
			TraceEvent(SevSample, "Promise_send").log();
		this->mutex.enter();
		if (!canBeSetUnsafe()) {
			this->mutex.leave();
			ASSERT(false); // Promise fulfilled twice
		}
		this->value = value; //< Danger: polymorphic operation inside lock
		this->status = Set;
		if (!callback) {
			this->mutex.leave();
			return;
		}

		auto func = callback;
		if (!callback->isMultiCallback())
			callback = nullptr;

		if (!func->canFire(0)) {
			this->mutex.leave();
		} else {
			this->mutex.leave();

			// Thread safe because status is now Set and callback is nullptr, meaning than callback cannot change
			int userParam = 0;
			func->fire(Void(), userParam);
		}
	}

	void cleanupUnsafe() override {
		value = T();