When there is a value from input, or the reactive is pinged, this reactive emits the result of fn.
input
fn
fn is provided the previous value as well as the most recent value.
If no previous value is available, the current value is emitted and fn is not called.
When there is a value from
input, or the reactive is pinged, this reactive emits the result offn.fnis provided the previous value as well as the most recent value.If no previous value is available, the current value is emitted and
fnis not called.