Tutorial by Examples: r

Below is example of service decorator, overriding null date returned by service. angular.module('app', []) .config(function($provide) { $provide.decorator('myService', function($delegate) { $delegate.getDate = function() { // override with actual date object return new Date(...

The standard Ada programming language is defined in the Ada Reference Manual. Interim version changes and release notes are discussed in the corresponding rationale documents. Implementations typically document their compliance with the standard in the form of a user guide and/or reference manual, f...

To remove all elements from a Map, use the .clear() method: map.clear(); Example: const map = new Map([[1, 2], [3, 4]]); console.log(map.size); // 2 map.clear(); console.log(map.size); // 0 console.log(map.get(1)); // undefined

To remove an element from a map use the .delete() method. map.delete(key); Example: const map = new Map([[1, 2], [3, 4]]); console.log(map.get(3)); // 4 map.delete(3); console.log(map.get(3)); // undefined This method returns true if the element existed and has been removed, otherwise fal...

Map has three methods which returns iterators: .keys(), .values() and .entries(). .entries() is the default Map iterator, and contains [key, value] pairs. const map = new Map([[1, 2], [3, 4]]); for (const [key, value] of map) { console.log(`key: ${key}, value: ${value}`); // logs: // ke...

To get the numbers of elements of a Map, use the .size property: const map = new Map([[1, 2], [3, 4]]); console.log(map.size); // 2

To enable code shrinking with ProGuard, add minifyEnabled true to the appropriate build type in your build.gradle file. android { buildTypes { release { minifyEnabled true proguardFiles getDefaultProguardFile(‘proguard-android.txt'), 'pro...

To enable resource shrinking, set the shrinkResources property to true in your build.gradle file. android { ... buildTypes { release { minifyEnabled true shrinkResources true proguardFiles getDefaultProguardFile('proguard-android.txt'), 'p...

All libraries come with resources that are not necessary useful to your application. For example Google Play Services comes with translations for languages your own application don’t even support. You can configure the build.gradle file to specify which resource you want to keep. For example: de...

Setting the state of an object graph (a collection of related entities) to Added is different than setting a single entity as Added (see this example). In the example, we store planets and their moons: Class model public class Planet { public Planet() { Moons = new HashSet<...

Using requestAnimationFrame may on some systems update at more frames per second than the 60fps. 60fps is the default rate if the rendering can keep up. Some systems will run at 120fps maybe more. If you use the following method you should only use frame rates that are integer divisions of 60 so th...

An implicitly-typed local variable that is strongly typed just as if the user had declared the type. Unlike other variable declarations, the compiler determines the type of variable that this represents based on the value that is assigned to it. var i = 10; // implicitly typed, the compiler must de...

Building project dependencies can sometimes be a tedious task. Instead of publishing a package version to NPM and installing the dependency to test the changes, use npm link. npm link creates a symlink so the latest code can be tested in a local environment. This makes testing global tools and proje...

R provides two additional looping constructs, while and repeat, which are typically used in situations where the number of iterations required is indeterminate. The while loop The general form of a while loop is as follows, while (condition) { ## do something ## in loop body } whe...

First, let's see three different ways of extracting data from a file. string fileText = File.ReadAllText(file); string[] fileLines = File.ReadAllLines(file); byte[] fileBytes = File.ReadAllBytes(file); On the first line, we read all the data in the file as a string. On the second line, we r...

Iterating over connected serial ports using System.IO.Ports; string[] ports = SerialPort.GetPortNames(); for (int i = 0; i < ports.Length; i++) { Console.WriteLine(ports[i]); } Instantiating a System.IO.SerialPort object using System.IO.Ports; SerialPort port = new SerialPort(); ...

This example is about replacing a List element while ensuring that the replacement element is at the same position as the element that is replaced. This can be done using these methods: set(int index, T type) int indexOf(T type) Consider an ArrayList containing the elements "Program sta...

A conversion that involves calling an explicit constructor or conversion function can't be done implicitly. We can request that the conversion be done explicitly using static_cast. The meaning is the same as that of a direct initialization, except that the result is a temporary. class C { std:...

static_cast can perform any implicit conversion. This use of static_cast can occasionally be useful, such as in the following examples: When passing arguments to an ellipsis, the "expected" argument type is not statically known, so no implicit conversion will occur. const double x = ...

For a class Person like: public class Person { public string Name { get; set; } public int Age { get; set; } public string Clothes { get; set; } } var person1 = new Person { Name = "Jon", Age = 20, Clothes = "some clothes" }; var person2 = new Person { Name ...