woh,i am a newbiez.Getting a hard time in polymorphism,are they anyone who provides a good example of it? at least some good explanation and example coding for it. i will be grateful.
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woh,i am a newbiez.Getting a hard time in polymorphism,are they anyone who provides a good example of it? at least some good explanation and example coding for it. i will be grateful.
Polymorphism is the ability for different objects to share the same interface, but the implementation mean by different. I guess a good example would be a stream object, where one implementation represented a memory stream, while the other is a file stream.
Here's a definition from Foldoc:
A concept first identified by Christopher Strachey (1967) and developed by Hindley and Milner, allowing types such as list of anything. E.g. in {Haskell}:
length :: [a] -> Int
is a function which operates on a list of objects of any type, a (a is a type variable). This is known as parametric polymorphism. Polymorphic typing allows strong type checking as well as generic functions. {ML} in 1976 was the first language with polymorphic typing.
Ad-hoc polymorphism (better described as {overloading}) is the ability to use the same syntax for objects of different types, e.g. "+" for addition of reals and integers or "-" for unary negation or diadic subtraction. Parametric polymorphism allows the same object code for a function to handle arguments of many types but overloading only reuses syntax and requires different code to handle different types.
See also {generic type variable}.
In {object-oriented programming}, the term is used to describe variables which may refer at run time to objects of different {class}es.