# getEdge

Get an edge's data.

## Signatures

```ts
export declare const getEdge: {
    (edgeIndex: Graph.EdgeIndex): <N, E, T extends Graph.Kind, Err, R>(ref: RefGraph<N, E, T, Err, R>) => RefSubject.Filtered<Graph.Edge<E>, Err, R>;
    <N, E, T extends Graph.Kind, Err, R>(ref: RefGraph<N, E, T, Err, R>, edgeIndex: Graph.EdgeIndex): RefSubject.Filtered<Graph.Edge<E>, Err, R>;
};
```

## Why

Models the possibly absent result of get edge as Filtered state, so absence stays explicit while
later source versions can make a value available.

## Ownership and lifetime

The get edge view retains no independent value. Its Effect read fails with NoSuchElement
while absent; the observing Scope owns and finalizes its Fx subscription.