NAME

SPVM::Comparator - Interface Type for Object Comparation Callback

SYNOPSYS

use Comparator;
use Point;

my $comparator = (Comparator)method : int ($object1 : object, $object2 : object); {
  my $point1 = (Point)$object1;
  my $point2 = (Point)$object2;
  
  if ($point1->x > $point2->x) {
    return 1;
  }
  elsif ($point1->x < $point2->x) {
    return -1;
  }
  else {
    return 0;
  }
};

my $point1 = Point->new_xy(1, 2);
my $point2 = Point->new_xy(5, 6);
my $result = $comparator->($point1, $point2);

DESCRIPTION

Comparator is the interface type for the object comparation callback.

INTERFACE METHODS

required method : int ($object1 : object, $object2 : object);

This method must receive two objects and return the following value.

If the first argument is greater than the second argument, returns 1. If the first argument is lower than the second argument, returns -1. If the first argument is equal to the second argument, returns 0.