[API reference](https://evolu.dev/docs/api-reference) › [@evolu/common](https://evolu.dev/docs/api-reference/common) › [Set](https://evolu.dev/docs/api-reference/common/Set) › firstInSet

```ts
function firstInSet<T>(set: NonEmptyReadonlySet<T>): T;
```

Defined in: [packages/common/src/Set.ts:314](https://github.com/evoluhq/evolu/blob/037c390af081e9944d616ff298a729515c5c5ab7/packages/common/src/Set.ts#L314)

Returns the first element of a non-empty set (by insertion order).

### Reading the first value

```ts

const set = createSet(["a", "b", "c"]);
assertEqual(firstInSet(set), "a");
```