"Steve Chow" <robertogoberto@gmail.com> wrote in message
news:17d61f66-0685-42e3-9b20-5103cb58f12c@r1g2000yqj.googlegroups.com...
Originally I had a bunch of related functions that all took a vector
of Point2D as their argument.
Point2D findGreatestDistance(std::vector<Point2D>& points);
However, this didn't strike me as a very C++/OO way to do things, so I
found a solution I was happy with in:
class Path : public std::vector<Point2D>
{
public:
Path();
~Path();
Point2D findGreatestDistance();
/* related functions */
};
And it works, at least as far as I can tell. Yet it's been received by
people more knowledgeable than me as disgusting and wrong, without
explaining why. Is there a better way I should be doing this?
Someone suggested moving findGreatestDistance into Point2D (struct
with x,y and overload ==) but I don't see how that's possible because
it'd only be able to look at itself.
No in general it is not bad practice, Stroustrup does it in The C++
Programming Language (25.6.1 Adjusting Interfaces). The only thing you
have to watch out for is that a standard container's destructor is not
virtual.
See http://www.i42.co.uk/stuff/mutable_set.htm also (something I wrote
but deriving from map/multimap instead of vector).
(i.e. you are simply performing interface augmentation).