# `CollectionOptions.attachTo`

> Contract 2.0.0 · package sha256 `a857eca95b35921109faf997094bb4192f12527d9d0fcd4be7e97f06425bad6e` · generated from `configurator-runtime.d.ts` by `services/onsite-scripter/scripts/build-contract-docs.mjs`; edit the source, not this file.

Property of [`CollectionOptions`](CollectionOptions.md) · stable · since 2.0.0

```ts
attachTo?: Query;
```

Follow this part: re-attached after reloads. Its items' `at` are in that part's frame, so they draw and read where it is drawn, move with it and hide while it is hidden; while no part matches, or only this collection's own parts do, they are in the world, and a query that matches several parts attaches nothing ('target-ambiguous'). Applies at creation only; on a live name, an omitted `attachTo` is no check and a different one throws 'collection-options-mismatch'.

**Default:** undefined (world)

## Generic-API test (spec 3.1)

| Rule | Result |
| --- | --- |
| 1. Neutral name | pass: `attachTo` names no product |
| 2. A precedent | not recorded: no ledger row (coverage.json) names this member or its owner |
| 3. Two apps, or labs | not recorded: no ledger row names this member or its owner |
| 4. The cheaper fix first | not recorded per member (Appendix B decides it per need) |