Classes

[Denis McMahon]

On Sun, 02 Nov 2014 11:31:12 -0500, Dennis Lee Bieber wrote:

> On Sun, 2 Nov 2014 12:27:06 +0000 (UTC), Denis McMahon
> <denismfmcmahon at gmail.com> declaimed the following:
> 
>>On Sun, 02 Nov 2014 21:32:13 +1100, Tim Delaney wrote:

>>> If course, that's probably because rectangles have a multitude of uses
>>> for user interfaces, whilst other quadrilaterals are somewhat less
>>> useful.
>>
>>And perhaps that also addresses the square - rectangle (or circle -
>>ellipse) issue - square, rectangle and rhombus are all forms of
>>quadrilateral, and perhaps should all inherit a base class
>>Quadrilateral,
>>rather than trying (and partially failing) to inherit each other.
> 
> 	I'd class them as parallelograms -- as they differ from a 
trapezoid in
> that opposite faces are parallel... Not to mention "arrow heads" where
> two adjacent sides actually bend inwards.

So:

Quadrilateral
    Parallelogram
        Square
        Rectangle
        Rhombus
        Diamond (4 sides eq)
    Trapezoid
        Arrowhead

Is an arrowhead a trapezoid?

-- 
Denis McMahon, denismfmcmahon at gmail.com