Properties

❗️info

Here are valuable properties of the Computed Class listed, which aren't directly related to the State Class.

The Computed is an extension of the State Class and offers the same properties as a normal State. These State related properties aren't described in this Section. To find out more about specific State properties, check out the State documentation.

computeFunction

Method used to compute the value of the Computed Class.

const MY_COMPUTED = createComputed(() => 1 + 1);
MY_COMPUTED.computeFunction(); // Returns '2'
MY_COMPUTED.value; // Returns '2'

This function will be called on each dependency mutation. Dependencies can for example be States or Collections. In the above code snippet MY_COMPUTED is independent, but in the blow example it depends on the MY_NAME and MY_AGE State.

const MY_COMPUTED = createComputed(() => {
    return `My name is '${MY_NAME.value}' and I am ${MY_AGE.value} years old.`;
});
MY_COMPUTED.value; // Returns "My name is 'jeff' and I am 10 years old"
MY_NAME.set('hans');
// Internally calls compute function
MY_COMPUTED.value; // Returns "My name is 'hans' and I am 10 years old"

📄 Return

() => ComputedValueType

---

deps

An Array of Observers the Computed Class depends on.

const MY_COMPUTED = createComputed(() => {
    return MY_NAME.value + MY_AGE.value;
}, [MY_LOCATION]);

MY_COMPUTED.deps; // Returns (see below)
// [Observer(MY_LOCATION), Observer(MY_NAME), Observer(MY_AGE)]

It does include the auto-detected Observers (MY_NAME, MY_AGE) and the hard-coded Observers (MY_LOCATION). If any of these dependencies mutates, the Computed Class will recompute its value to stay up to date.

📄 Return

Array<Observer>

---

hardCodedDeps

An Array of hard-coded Observers the Computed Class depends on.

const MY_COMPUTED = createComputed(() => {
    return MY_NAME.value + MY_AGE.value;
}, [MY_LOCATION]);

MY_COMPUTED.hardCodedDeps; // Returns (see below)
// [Observer(MY_LOCATION)]

📄 Return

Array<Observer>