Is Method Overloading considered polymorphism? [closed]

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Is Method Overloading considered part of polymorphism?

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There are different types of polymorphism:

• overloading polymorphism (also called Ad-hoc polymorphism)
• overriding polymorphism

So yes it is part of polymorphism.

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"Polymorphism" is just a word and doesn't have a globally agreed-upon, precise definition. You will not be enlightened by either a "yes" or a "no" answer to your question because the difference will be in the chosen definition of "polymorphism" and not in the essence of method overloading as a feature of any particular language. You can see the evidence of that in most of the other answers here, each introducing its own definition and then evaluating the language feature against it.

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Strictly speaking polymorphism, from wikipedia:

is the ability of one type, A, to appear as and be used like another type, B.

So, method overloading as such is not considered part of this definition polymorphism, as the overloads are defined as part of one type.

If you are talking about inclusion polymorphism (normally thought of as overriding), that is a different matter and then, yes it is considered to be part of polymorphism.

inclusion polymorphism is a concept in type theory wherein a name may denote instances of many different classes as long as they are related by some common super class.

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There are 2 types of polymorphism.

1. static
2. dynamic.

Overloading is of type static polymorphism.. overriding comes under dynamic (or run-time) polymorphism..

ref. http://en.wikipedia.org/wiki/Polymorphism_(computer_science) which describes it more.

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No, overloading is not. Maybe you refer to method overriding which is indeed part of polymorphism.

To further clarify, From the wikipedia:

Polymorphism is not the same as method overloading or method overriding.1 Polymorphism is only concerned with the application of specific implementations to an interface or a more generic base class.

So I'd say method overriding AND method overloading and convenient features of some language regarding polymorphism but notthe main concern of polymorphism (in object oriented programming) which only regards to the capability of an object to act as if it was another object in its hierarchy chain.

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Method overriding or overloading is not polymorphism. The right way to put it is that Polymorphism can be implemented using method overriding or overloading and using other ways as well.

In order to implement Polymorphism using method overriding, you can override the behaviour of a method in a sub-class.

In order to implement Polymorphism using method overloading, you need to write many methods with the same name and the same number of parameters but with different data types and implement different behavious in these methods. Now that is also polymorphism.

Other ways to implement polymorphism is operator overloading and implementing interfaces.

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Wikipedia pedantics aside, one way to think about polymorphism is: the ability for a single line of code / single method call to do different things at runtime depending on the type of the object instance used to make the call.

Method overloading does not change behaviors at runtime. Overloading gives you more choices for argument lists on the same method name when you're writing and compiling the code, but when it's compiled the choice is fixed in code forever.

Not to be confused with method overriding, which is part of polymorphism.

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It's a necessary evil that is and should only be used as a complement. In the end overloads should only convert and eventually forward to the main method. OverloDing is necessary because most vms for staticalky dispatched environments don't know how to convert one type to another so the parameter fits the target and this is where one uses overloads to help out.

 StringBuilder
     Append(String) // main
     Append(Boolean) // converts and calls append(String)