Observation§

When Varying#react is called, an Observation ticket is returned. All it really contains is some tracking information, and a #stop method:

Reaction Management§

#stop§

.stop(): voidimpure

Stops the reaction associated with this Observation ticket.

const results = [];
const v = new Varying(1);
const observation = v.react(x => { results.push(x); });
v.set(2);
observation.stop();
v.set(3);
return results;