Class SnapshotResource

packages/core/src/resource/from_snapshots.ts:25–53

}

class SnapshotResource<T> implements Resource<T> {
  constructor(readonly snapshot: Signal<ResourceSnapshot<T>>) {}

  private get state(): ResourceSnapshot<T> {
    return this.snapshot();
  }

  readonly value = computed(() => {
    if (this.state.status === 'error') {
      throw new ResourceValueError(this.state.error);
    }
    return this.state.value;
  });
  readonly status = computed(() => this.state.status);
  readonly error = computed(() => (this.state.status === 'error' ? this.state.error : undefined));
  readonly isLoading = computed(
    () => this.state.status === 'loading' || this.state.status === 'reloading',
  );

  private isValueDefined = computed(
    () => this.state.status !== 'error' && this.state.value !== undefined,
  );

  hasValue(this: T extends undefined ? this : never): this is Resource<Exclude<T, undefined>>;
  hasValue(): boolean;
  hasValue(): boolean {
    return this.isValueDefined();
  }
}