ConstSignal
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package events
If this signal is computed from sources that change their value via a side effect (such as signals) and is not informed of those changes while unwired (e.g.
If this signal is computed from sources that change their value via a side effect (such as signals) and is not informed of those changes while unwired (e.g. because this signal removes itself from the sources' children lists in #onUnwire), it is mandatory to update/recompute this signal's value from the sources in #onWire, since a dispatch always happens after #onWire. This is true even if the source values themselves did not change, for the recomputation in itself may rely on side effects (e.g. ZMessaging => SomeValueFromTheDatabase).
This also implies that a signal should never #dispatch in #onWire because that will happen anyway immediately afterwards in #subscribe.
Immutable signal value. Can be used whenever some constant or empty signal is needed. Using immutable signals in flatMap chains should have better performance compared to regular signals with the same value.