Tutorial by Examples: args

void doSomething(String... strings) { for (String s : strings) { System.out.println(s); } } The three periods after the final parameter's type indicate that the final argument may be passed as an array or as a sequence of arguments. Varargs can be used only in the final argume...

You can use the star * when writing a function to collect all positional (ie. unnamed) arguments in a tuple: def print_args(farg, *args): print("formal arg: %s" % farg) for arg in args: print("another positional arg: %s" % arg) Calling method: print_args(1, &...

You can define a function that takes an arbitrary number of keyword (named) arguments by using the double star ** before a parameter name: def print_kwargs(**kwargs): print(kwargs) When calling the method, Python will construct a dictionary of all keyword arguments and make it available in ...

A common use case for *args in a function definition is to delegate processing to either a wrapped or inherited function. A typical example might be in a class's __init__ method class A(object): def __init__(self, b, c): self.y = b self.z = c class B(A): def __init__(...

You can use a dictionary to assign values to the function's parameters; using parameters name as keys in the dictionary and the value of these arguments bound to each key: def test_func(arg1, arg2, arg3): # Usual function with three arguments print("arg1: %s" % arg1) print("a...

The effect of using the * operator on an argument when calling a function is that of unpacking the list or a tuple argument def print_args(arg1, arg2): print(str(arg1) + str(arg2)) a = [1,2] b = tuple([3,4]) print_args(*a) # 12 print_args(*b) # 34 Note that the length of the starr...

Custom events usually need custom event arguments containing information about the event. For example MouseEventArgs which is used by mouse events like MouseDown or MouseUp events, contains information about Location or Buttons which used to generate the event. When creating new events, to create a...

Using varargs as a parameter for a method definition, it is possible to pass either an array or a sequence of arguments. If a sequence of arguments are passed, they are converted into an array automatically. This example shows both an array and a sequence of arguments being passed into the printVar...

All of these main method styles can also be used with varargs: package my.program fun main(vararg args: String) { println("Hello, world!") }

To use default values with **kwargs def fun(**kwargs): print kwargs.get('value', 0) fun() # print 0 fun(value=1) # print 1

You can get easily get this information by barfing out the input in your handler function. For example, in Java: public String handleRequest(String input, Context context) { context.getLogger().log("Input: " + input); String output = "Input:" + System.getProperty(&qu...

You can access the command line arguments passed to your program using the std::env::args() function. This returns an Args iterator which you can loop over or collect into a Vec. Iterating Through Arguments use std::env; fn main() { for argument in env::args() { if argument == &qu...

$Args Contains an array of the undeclared parameters and/or parameter values that are passed to a function, script, or script block. When you create a function, you can declare the parameters by using the param keyword or by adding a comma-separated list of parameters in parentheses after the...