Effects that write signals
A write made by an effect re-queues its readers; they run in a later pass of the same flush, after the pass that is draining.
A write made by an effect re-queues its readers; they run in a later pass of the same flush, after the pass that is draining. The flush ends when no effect is pending.
Prefer a memo when a value is a pure function of other values: a memo needs no extra pass, and writing a signal inside one is an error (see WRITE_IN_MEMO).