Function syncWatchValue

Watches a single reactive value and executes a callback whenever that value changes.

This function is the synchronous variant of watchValue. It will re-execute after every fine grained change, even if those changes occur in immediate succession. syncWatchValue should therefore be considered a low level primitive, for most use cases watchValue should be the right tool instead.

Example:

import { reactive, syncWatchValue } from "@conterra/reactivity-core";

const v1 = reactive(1);
const v2 = reactive(2);

// Executes whenever the _sum_ of the two values changes.
syncWatchValue(() => v1.value + v2.value, (sum) => {
    console.log("new sum", sum);
});
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syncWatchValue returns a handle that can be used to unsubscribe from changes. That handle's destroy() function should be called to stop watching when you are no longer interested in updates:

const handle = syncWatchValue(() => someReactive.value, () => {
  // ...
});
// later:
handle.destroy();
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NOTE: You must not modify the parameters that get passed into callback.

This overload is used when immediate is not set to false.