# RefTuple.appendElement

Append an element to the end of the current state of a RefTuple.

## Signatures

```ts
export declare const appendElement: {
    <E>(element: E): <T extends ReadonlyArray<unknown>, Err, R>(ref: RefTuple<T, Err, R>) => RefSubject.Computed<[
        ...T,
        E
    ], Err, R>;
    <T extends ReadonlyArray<unknown>, E, Err, R>(ref: RefTuple<T, Err, R>, element: E): RefSubject.Computed<[
        ...T,
        E
    ], Err, R>;
};
```

## Why

Expresses append element as one ordered tuple transition; readers never observe the intermediate
collection used to build the result.

## Ownership and lifetime

The append element view retains no independent state. An Effect read samples the source once; Fx
observation follows later pushes and its observing Scope owns subscription cleanup.