/* comparable.vala
*
* Copyright (C) 2009 Didier Villevalois
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*
* Author:
* Didier 'Ptitjes Villevalois <ptitjes@free.fr>
*/
/**
* This interface defines a total ordering among instances of each class
* implementing it.
*
* In other words:
*
* * It's irreflexive: For all `a` it holds that `a.compare_to(a) == 0`
* * It's transitive: For all `a`, `b` and `c` if `a.compare_to(b) < 0` and
* `b.compare_to(c) < 0` then `a.compare_to(c) < 0`.
* * It's trichotomous: For all `a` and `b` it holds that
* `a.compare_to(b) = -b.compare_to(a)`.
*
* Note: The relationship must be immutable. In other words if at one point of
* program `a.compare_to(b)` had certain value then call `a.compare_to(b)`
* //must always// return the original value until end of `a` and `b` lifetime.
*
* @see Hashable
*/
public interface Gee.Comparable<G> : Object {
/**
* Compares this object with the specifed object.
*
* @return a negative integer, zero, or a positive integer as this object
* is less than, equal to, or greater than the specified object
*/
public abstract int compare_to (G object);
}