Computed Properties

Computed properties allow you to define state derivations that are cached and automatically updated whenever their source dependencies change.

Definition

Define a computed property using the <computed /> tag. It accepts a name and an expression:

<state price="100" tax="0.1" />
<computed name="taxAmount" value="price * tax" />
<computed name="totalPrice" value="price + taxAmount" />

Dependency Tracking & Caching

The reactivity system automatically traces which properties are read during the evaluation of a computed getter. It builds a dependency graph dynamically.

• If the variables referenced (e.g. price or tax) do not change, accessing the computed property returns the cached value instantly without re-evaluation.

• When a dependency changes, the computed property is marked as dirty, triggering updates in any views or downstream computed properties depending on it.

Circular Dependency Protection

If you accidentally introduce a recursive loop (e.g., computed property a depends on b, which depends on a), Avenx detects it immediately during evaluation, cancels the infinite loop, throws warning code [AVX_R04], and returns undefined to keep the application stable.