Tutorial by Examples: argument

You define a keyword argument in a method by specifying the name in the method definition: def say(message: "Hello World") puts message end say # => "Hello World" say message: "Today is Monday" # => "Today is Monday" You can define multip...
2.1 Required keyword arguments were introduced in Ruby 2.1, as an improvement to keyword arguments. To define a keyword argument as required, simply declare the argument without a default value. def say(message:) puts message end say # => ArgumentError: missing keyword: message say ...
You can define a method to accept an arbitrary number of keyword arguments using the double splat (**) operator: def say(**args) puts args end say foo: "1", bar: "2" # {:foo=>"1", :bar=>"2"} The arguments are captured in a Hash. You can manip...
Use the curry function (from Prelude or Data.Tuple) to convert a function that takes tuples to a function that takes two arguments. curry fst 1 2 -- computes 1 curry snd 1 2 -- computes 2 curry (uncurry f) -- computes the same as f import Data.Tuple (swap) curry swap 1 2 -- computes (2, 1...
If you want to parse more complex command-line arguments, e.g. with optional parameters, than the best is to use google's GWT approach. All classes are public available at: https://gwt.googlesource.com/gwt/+/2.8.0-beta1/dev/core/src/com/google/gwt/util/tools/ToolBase.java An example for handling ...
If a function has multiple arguments, it is unspecified what order they are evaluated in. The following code could print x = 1, y = 2 or x = 2, y = 1 but it is unspecified which. int f(int x, int y) { printf("x = %d, y = %d\n", x, y); } int get_val() { static int x = 0; r...
A simple example which provides the options: OptAlt. OptDetails-h--helpShow help-v--versionShow version info-dr path--doc-root pathAn option which takes a secondary parameter (a path)-i--installA boolean option (true/false)-*--Invalid option #!/bin/bash dr='' install=false skip=false for op ...
def hello_world(greeting: str = 'Hello'): print(greeting + ' world!') Note the spaces around the equal sign as opposed to how keyword arguments are usually styled.
If you have void F1(MyType1 x) { // do something } void F1(MyType2 x) { // do something else } and for some reason you need to call the first overload of F1 but with x = null, then doing simply F1(null); will not compile as the call is ambiguous. To counter this you can do F1...
When the command-line syntax for an application is simple, it is reasonable to do the command argument processing entirely in custom code. In this example, we will present a series of simple case studies. In each case, the code will produce error messages if the arguments are unacceptable, and the...
First of all, the problem of handling spaces in arguments is NOT actually a Java problem. Rather it is a problem that needs to be handled by the command shell that you are using when you run a Java program. As an example, let us suppose that we have the following simple program that prints the siz...
A question that occasionally on StackOverflow is whether it is appropriate to use assert to validate arguments supplied to a method, or even inputs provided by the user. The simple answer is that it is not appropriate. Better alternatives include: Throwing an IllegalArgumentException using cust...
In many application it is necessary to compute the function of two or more arguments. Traditionally, we use for-loops. For example, if we need to calculate the f = exp(-x^2-y^2) (do not use this if you need fast simulations): % code1 x = -1.2:0.2:1.4; y = -2:0.25:3; for nx=1:lenght(x) for n...
Though Go supports ++ and -- operators and the behaviour is found to be almost similar to c/c++, variables with such operators cannot be passed as argument to function. package main import ( "fmt" ) func abcd(a int, b int) { fmt.Println(a," &...
SASS's optional arguments let you use a parameter only if you specify its value; otherwise, it will be ignored. Let's take an example of the following mixin: @mixin galerie-thumbnail ($img-height:14em, $img-width: null) { width: $img-width; height: $img-height; outline: 1px solid li...
type Dog = Dog String dogName1 dog = case dog of Dog name -> name dogName2 (Dog name) -> name dogName1 and dogName2 are equivalent. Note that this only works for ADTs that have a single constructor. type alias Pet = { name: String , weight: Float ...
Some programs need so store arguments for future calling of some function. This example shows how to call any function with arguments stored in std::tuple #include <iostream> #include <functional> #include <tuple> #include <iostream> // simple function to be called d...
The subprocess method that allows running commands needs the command in form of a list (at least using shell_mode=True). The rules to create the list are not always straightforward to follow, especially with complex commands. Fortunately, there is a very helpful tool that allows doing that: shlex. ...
interface Mockable { bool DoSomething(); } var mock = new Mock<Mockable>(); mock.Setup(x => x.DoSomething()).Returns(true); var result = mock.Object.DoSomething(); //true
Where command line arguments are supported they can be read in via the get_command_argument intrinsic (introduced in the Fortran 2003 standard). The command_argument_count intrinsic provides a way to know the number of arguments provided at the command line. All command-line arguments are read in ...

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