Functions can be declared, in the global context or class context. Functions in classes are commonly called methods. See Variables, Scope and Runtime Contexts for variable scopes.
Any function calls can take any number of parameters. In a function/method declaration, the
named parameters can be used in the code as local variables. If not enough number of parameters
are specified at the runtime, null is used for the missing values. If there are more than
the declared parameters, those extra parameters (beyond the declared ones) are accessed via the
built-in array
For class methods, data members should be accessed with this
A class method is overridden by a same-name method in a derived class. The code in the
child class method can invoke the parent's same-name method with the prefix super