define polymorphism

[E. Robert Tisdale]

polymorph just means "many form(s)".
The definition in plain English

http://www.bartleby.com/61/66/P0426600.html

and narrower definitions in the context of computer programming

http://en.wikipedia.org/wiki/Polymorphism
http://wombat.doc.ic.ac.uk/foldoc/foldoc.cgi?query=polymorphism&action=Search

don't really help us understand what polymorphism means
in the context of the C++ computer programming language.

Simple operator overloading could be polymorphism.
Generic programming with templates could be polymorphism.
Or polymorphism may be restricted specifically
to run-time (dynamic binding) of a function call to it's implementation
(virtual functions).

 

[EventHelix.com]

In general usage of the term, it refers to inheritance with runtime
binding.

The Liskov Substitution Principle would be a good explaination of
polymorphism:
http://www.eventhelix.com/RealtimeMantra/Object_Oriented/liskov_substitution_principle.htm

Deepa

 

[Rolf Magnus]

polymorph just means "many form(s)".
The definition in plain English

http://www.bartleby.com/61/66/P0426600.html

and narrower definitions in the context of computer programming

http://en.wikipedia.org/wiki/Polymorphism
http://wombat.doc.ic.ac.uk/foldoc/foldoc.cgi?query=polymorphism&action=Search

don't really help us understand what polymorphism means
in the context of the C++ computer programming language.

Simple operator overloading could be polymorphism.

That's not considered to be polymorphism.

Generic programming with templates could be polymorphism.

That is sometimes called "compile-time polymorphism".

Or polymorphism may be restricted specifically
to run-time (dynamic binding) of a function call to it's implementation
(virtual functions).

This is what is usually meant by the term "polymorphism".

 

[Dave O'Hearn]

polymorph just means "many form(s)".
The definition in plain English

and narrower definitions in the context of computer programming
[urls]
don't really help us understand what polymorphism means
in the context of the C++ computer programming language.

Simple operator overloading could be polymorphism.
Generic programming with templates could be polymorphism.
Or polymorphism may be restricted specifically
to run-time (dynamic binding) of a function call to it's
implementation (virtual functions).

I liked the wiki's description. It would put overloading as a form of
ad-hoc polymorphism, templates as parametric polymorphism, and virtual
functions as subtyping polymorphism.

I have heard templates referred to as "parametric polymorphism" in a
lot of places. Stroustrup does it on page 347 of TC++PL, and Google
gives a lot of matches for (templates "parametric polymorphism"). So
that seems already to be accepted.

The wiki's terminology of "ad hoc polymorphism" for overloading is
something I had never heard before, though. It doesn't really feel like
polymorphism to me. I usually consider overloading to be syntactic
sugar, if very useful syntactic sugar.[/QUOTE]