| advanced |

## CGAL::Partition_is_valid_traits_2<Traits, PolygonIsValid>

### Definition

Class that derives a traits class for partition_is_valid_2 from a given traits class by defining the validity testing function object in terms of a supplied template parameter.

#include <CGAL/Partition_is_valid_traits_2.h>

### Inherits From

Traits

### Is Model for the Concept

PartitionIsValidTraits_2

### Types

typedef PolygonIsValid
| Is_valid;
typedef Traits::Point_2
| Point_2;
typedef Traits::Polygon_2
| Polygon_2;
typedef Traits::Less_xy_2
| Less_xy_2;
typedef Traits::Left_turn_2
| Left_turn_2;
typedef Traits::Orientation_2
| Orientation_2;

### Operations

The constructors and member functions for creating instances of the above types are inherited from Traits. In addition, the following member function is defined:

Is_valid | traits.is_valid_object ( Traits traits)
|  | function returning an instance of Is_valid

### See Also

CGAL::Is_convex_2<Traits>
CGAL::Is_vacuously_valid<Traits>
CGAL::Is_y_monotone_2<Traits>
CGAL::Partition_traits_2<R>

### Example

See the example presented with the function optimal_convex_partition_2 for an illustration of the use of this traits class.

| advanced |