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The when-statement is an alternative to an if-statement with multiple else-if-branches: when { str.length == 0 -> print("The string is empty!") str.length > 5 -> print("The string is short!") else -> print("The string is long!") ...

When given an argument, the when-statement matches the argument against the branches in sequence. The matching is done using the == operator which performs null checks and compares the operands using the equals function. The first matching one will be executed. when (x) { "English" -...

Like if, when can also be used as an expression: val greeting = when (x) { "English" -> "How are you?" "German" -> "Wie geht es dir?" else -> "I don't know that language yet :(" } print(greeting) To be used as an express...

(This pitfall applies equally to all primitive wrapper types, but we will illustrate it for Integer and int.) When working with Integer objects, it is tempting to use == to compare values, because that is what you would do with int values. And in some cases this will seem to work: Integer int1_1 =...

1. Fix your contexts: Try using the appropriate context: For example since a Toast can be seen in many activities instead of in just one, use getApplicationContext() for toasts, and since services can keep running even though an activity has ended start a service with: Intent myService = new Inten...

The .format() method can interpret a number in different formats, such as: >>> '{:c}'.format(65) # Unicode character 'A' >>> '{:d}'.format(0x0a) # base 10 '10' >>> '{:n}'.format(0x0a) # base 10 using current locale for separators '10' Format integers to d...

union U { int a; short b; float c; }; U u; u.a = 10; if (u.b == 10) { // this is undefined behavior since 'a' was the last member to be // written to. A lot of compilers will allow this and might issue a // warning, but the result will be "as expected"; thi...

Properties can be set when an object is instantiated. var redCar = new Car { Wheels = 2, Year = 2016, Color = Color.Red };

functions.php //Localize the AJAX URL and Nonce add_action('wp_enqueue_scripts', 'example_localize_ajax'); function example_localize_ajax(){ wp_localize_script('jquery', 'ajax', array( 'url' => admin_url('admin-ajax.php'), 'nonce' => wp_create_nonce('example_ajax_nonc...

If you know that a value is of a specific type, you can explicitly cast it to that type in order to use it in a context where that type is needed. object value = -1; int number = (int) value; Console.WriteLine(Math.Abs(number)); If we tried passing value directly to Math.Abs(), we would get a ...

If you aren't sure whether a value is of the type you think it is, you can safely cast it using the as operator. If the value is not of that type, the resulting value will be null. object value = "-1"; int? number = value as int?; if(number != null) { Console.WriteLine(Math.Abs(nu...

A value will automatically be cast to the appropriate type if the compiler knows that it can always be converted to that type. int number = -1; object value = number; Console.WriteLine(value); In this example, we didn't need to use the typical explicit casting syntax because the compiler knows...

If you need to know whether a value's type extends or implements a given type, but you don't want to actually cast it as that type, you can use the is operator. if(value is int) { Console.WriteLine(value + "is an int"); }

In the most basic form, it is possible to select a single variable from a table by calling the object's get_var method passing in an SQL query. global $wpdb; $user = $wpdb->get_var( "SELECT ID FROM $wpdb->users WHERE user_email='[email protected]'" ); It is very important to note that...

public class Singleton { private static class InstanceHolder { static final Singleton INSTANCE = new Singleton(); } public static Singleton getInstance() { return InstanceHolder.INSTANCE; } private Singleton() {} } This initializes the INSTANCE vari...

Prerequisites The Windows version of Elasticsearch can be obtained from this link: https://www.elastic.co/downloads/elasticsearch. The latest stable release is always at the top. As we are installing on Windows, we need the .ZIP archive. Click the link in the Downloads: section and save the file t...

add_action('init', 'process_post'); function process_post(){ if($_POST) var_dump($_POST); }

add_action('init' , function(){ echo 'i did something'; });

class sample{ public function __construct(){ add_action('init', array($this, 'samp') ); } public function samp(){ // must be public!! echo 'i did something'; } } new sample();

class sample{ public static function add_action_func(){ //note __CLASS__ will also include any namespacing add_action('init', array(__CLASS__, 'samp') ); } public static function samp(){ echo 'i did something'; } } sample::add_a...