graph-builder/markdown/graph-builder.basegraph.predecessors.md

A graph builder library for modeling abstract graph structures.

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# BaseGraph.predecessors method

Returns all nodes in this graph adjacent to `node` which can be reached by traversing `node`<!-- -->'s incoming edges <i>against</i> the direction (if any) of the edge.

In an undirected graph, this is equivalent to [BaseGraph.adjacentNodes](./graph-builder.basegraph.adjacentnodes.md)<!-- -->.

Throws an error if `node` is not an element of this graph.

**Signature:**
```javascript
predecessors(node: N): Set<N>;
```
**Returns:** `Set<N>`

## Parameters

|  Parameter | Type | Description |
|  --- | --- | --- |
|  `node` | `N` |  |