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Version: 2.0.0

Constant Fields

A constant field is a purely output field whose value is set once at creation and never changes. Input values and updates are ignored.

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Default values​

The constant value can be static or a resolver function. Resolvers receive the creation context and are evaluated once, when the entity is created.

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If a resolver throws, the field value becomes null.

Hooks​

Constant fields support onDelete and onSuccess listeners.

b.constant("id", () => "user-123")
  .onDelete((entity) => console.log("deleted", entity.id))
  .onSuccess((summary) => console.log("created", summary.values.id));

API summary​

MethodDescription
constant(name, value)Create a constant field with a static value or resolver.
onDelete(handler)Listener invoked by model.delete.
onSuccess(handler)Listener invoked after a successful create/update.