## ArrangementDcelHalfedge_2

### Definition

A model of the ArrangementDcelHalfedge_2 concept is a halfedge of the Dcel of the arrangement data structure.

An ArrangementDcelHalfedge_2 is not (!) a refinement of the PlanarMapDcelHalfedge_2 concept . However, it is very similar.

The concept has an additional type Base_node which should be the same as the template parameter Base_node of the arrangement (see section ). It has the additional methods edge_node() and set_edge_node(Base_node*).

The method set_curve should do nothing, i.e. be empty. The function is needed to satisfy a syntactical requirement.

### Definition

### Operations

Base_node* | e.edge_node () | returns a pointer to the edge node in the hierarchy tree which holds the curve from which the halfedge was generated.
void | e.set_edge_node ( Base_node* b)
|  | sets b to be the edge node in the hierarchy tree which holds the curve of the halfedge.
void | e.set_curve ( Curve cv)
|  | should do nothing.

### Has Models

CGAL::Arr_2_halfedge_base<Base_node> (for example, used by Arr_2_default_dcel<Traits> )