RosettaCodeData/Task/Function-prototype/00DESCRIPTION

Some languages provide the facility to declare functions and subroutines through the use of [[wp:Function prototype|function prototyping]].


;Task:
Demonstrate the methods available for declaring prototypes within the language. The provided solutions should include:

* An explanation of any placement restrictions for prototype declarations
* A prototype declaration for a function that does not require arguments
* A prototype declaration for a function that requires two arguments
* A prototype declaration for a function that utilizes varargs
* A prototype declaration for a function that utilizes optional arguments
* A prototype declaration for a function that utilizes named parameters
* Example of prototype declarations for subroutines or procedures (if these differ from functions)
* An explanation and example of any special forms of prototyping not covered by the above

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Languages that do not provide function prototyping facilities should be omitted from this task.
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