Re: Some thoughts on polymorphism

From:

=?iso-8859-1?q?Kirit_S=E6lensminde?= <kirit.saelensminde@gmail.com>

Newsgroups:

comp.lang.c++

Date:

2 May 2007 20:37:56 -0700

Message-ID:

<1178163476.724423.204640@n76g2000hsh.googlegroups.com>

On May 3, 12:51 am, faceman28...@yahoo.com wrote:

On May 1, 11:43 pm, chsal...@gmail.com wrote:

I've been programming in C++ for a little over 2 years, and I still
find myself wondering when I should use polymorphism.

The reality is polymorphism really doesn't show great value unless you
have a sufficent number number of related classes. Thus most academic
examples are pretty worthless.

In some ways it is only a minor point, but polymorphism isn't
inheritance, although inheritance is a form of polymorphism. There are
many other polymorphic constructs in C++.

std::list (and the rest of the STL containers) are polymorphic
classes. std::max is a polymorphic function as are the ones in
<algorithm>. Even the C operator + (which C++ inherits) is
polymorphic.

There are lots and lots of forms of polymorphism and many of them can
be used in C++ (but not all of them). Some of the ones that C++
doesn't support are still very useful to understand. For example row
polymorphism can be used to analyse the type constraints that
templates impose.

K