Tutorial by Examples: w

6 When using arrow functions this takes the value from the enclosing execution context's this (that is, this in arrow functions has lexical scope rather than the usual dynamic scope). In global code (code that doesn't belong to any function) it would be the global object. And it keeps that way, eve...

We will further extend our template and include title of the page and a content <?php /* Template Name: Example */ get_header(); the_title(); the_content(); get_footer(); And if you want you can wrap them with HTML elements like this <?php /* Template Name: Example *...

Download Heroku Toolbelt. Navigate to the root of the sources of your Django app. You'll need tk Type heroku create [app_name]. If you don't give an app name, Heroku will randomly generate one for you. Your app URL will be http://[app name].herokuapp.com Make a text file with the ...

Values can be given names using let: # let a = 1;; val a : int = 1 You can use similar syntax to define a function. Just provide additional parameters for the arguments. # let add arg1 arg2 = arg1 + arg2;; val add : int -> int -> int = <fun> We can call it like this: # add 1...

The function keyword automatically has pattern matching when you define the body of your function. Observe it below: # let foo = function 0 -> "zero" | 1 -> "one" | 2 -> "couple" | 3 -> "few" | _ -> "many";; val foo : int -&gt...

A common use for enumerators is for switch statements and so they commonly appear in state machines. In fact a useful feature of switch statements with enumerations is that if no default statement is included for the switch, and not all values of the enum have been utilized, the compiler will issue ...

Enums in Swift are much more powerful than some of their counterparts in other languages, such as C. They share many features with classes and structs, such as defining initialisers, computed properties, instance methods, protocol conformances and extensions. protocol ChangesDirection { mutati...

package { import flash.events.TimerEvent; import flash.utils.Timer; public class CountdownTimer extends Timer { public var time:Number = 0; public function CountdownTimer(time:Number = Number.NEGATIVE_INFINITY, delay:Number = 1000) { super(delay, repeatCount); ...

Using functions that take in and execute closures can be extremely useful for sending a block of code to be executed elsewhere. We can start by allowing our function to take in an optional closure that will (in this case) return Void. func closedFunc(block: (()->Void)? = nil) { print("...

// RawRepresentable has an associatedType RawValue. // For this struct, we will make the compiler infer the type // by implementing the rawValue variable with a type of String // // Compiler infers RawValue = String without needing typealias // struct NotificationName: RawRepresentable { ...

With Gson, you can read JSON dataset and map them to a custom class MyClass. Since Gson is not serializable, each executor needs its own Gson object. Also, MyClass must be serializable in order to pass it between executors. Note that the file(s) that is offered as a json file is not a typical JSON...

There are several additional attributes that the Volley NetworkImageView adds to the standard ImageView. However, these attributes can only be set in code. The following is an example of how to make an extension class that will pick up the attributes from your XML layout file and apply them to the N...

A reference to an option &Option<T> cannot be unwrapped if the type T is not copyable. The solution is to change the option to &Option<&T> using as_ref(). Rust forbids transferring of ownership of objects while the objects are borrowed. When the Option itself is borrowed (&a...

A while loop will evaluate its condition, and if true, it will execute the code inside and start over. That is, as long as its condition evaluates to true, the while loop will execute over and over. This loop will execute 100 times, each time adding 1 to the variable num: int num = 0; while (nu...

A do while loop is the same as a while loop, except that it is guaranteed to execute at least one time. The following loop will execute 100 times. int i = 0; do { i++; } while (i < 100); A similar loop, but with a different condition, will execute 1 time. int i = 0; do { i++; ...

There are some ways to break or change a loop's flow. break; will exit the current loop, and will not execute any more lines within that loop. continue; will not execute any more code within the current iteration of the loop, but will remain in the loop. The following loop will execute 101 times ...

localStorage, sessionStorage are JavaScript Objects and you can treat them as such. Instead of using Storage Methods like .getItem(), .setItem(), etc… here's a simpler alternative: // Set localStorage.greet = "Hi!"; // Same as: window.localStorage.setItem("greet", "Hi!&qu...

This is a minimalist Hello World example that uses only the most basic Android tools. Requirements and assumptions Oracle JDK 1.7 or later Android SDK Tools (just the command line tools) This example assumes Linux. You may have to adjust the syntax for your own platform. Setting up the And...

A simple example on how to read a UTF text file synchronously. import flash.filesystem.File; import flash.filesystem.FileMode; import flash.filesystem.FileStream; //First, get a reference to the file you want to load var myFile:File = File.documentsDirectory.resolvePath("lifestory.txt&...

The most important AppWidgetProvider callback is onUpdate(). It is called everytime an appwidget is added. public class ExampleAppWidgetProvider extends AppWidgetProvider { public void onUpdate(Context context, AppWidgetManager appWidgetManager, int[] appWidgetIds) { final int N = a...