## ArrangementBaseNode_2

### Definition

A model for the ArrangementBaseNode_2 concept must provide the following types and operations. It defines the base class for the nodes of the hierarchy tree of the arrangement data structure CGAL::Arrangement_2<Dcel,Traits,Base_node>.

### Types

ArrangementBaseNode_2::Curve
| curve type, corresponding to the traits Curve type.

### Operations

Curve | bn.curve () | returns the curve in bn.
void | bn.set_curve ( Curve c)
|  | sets the curve in bn to c.

### Has Models

Arrangement_base_node<Curve>