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Using the Array::new constructor, your can initialize an array with a given size and a new array in each of its slots. The inner arrays can also be given a size and and initial value. For instance, to create a 3x4 array of zeros: array = Array.new(3) { Array.new(4) { 0 } } The array generated a...

Define your class that will represent your custom error. public class ErrorDto { public int Code { get; set; } public string Message { get; set; } // other fields public override string ToString() { return JsonConvert.SerializeObject(this); } } Then put nex...

The idea is to use HttpContext.Response.OnStarting callback, as this is the last event that is fired before the headers are sent. Add the following to your middleware Invoke method. public async Task Invoke(HttpContext context) { context.Response.OnStarting((state) => { if ...

A shell script is a very versatile way to extend your build to basically anything you can think of. As an exmaple, here is a simple script to compile protobuf files and add the result java files to the source directory for further compilation: def compilePb() { exec { // NOTICE: grad...

With the rgdal package it is possible to import and export shapfiles with R. The function readOGR can be used to imports shapfiles. If you want to import a file from e.g. ArcGIS the first argument dsn is the path to the folder which contains the shapefile. layer is the name of the shapefile without...

The packages foreign and haven can be used to import and export files from a variety of other statistical packages like Stata, SPSS and SAS and related software. There is a read function for each of the supported data types to import the files. # loading the packages library(foreign) library(have...

The class we are going to test is: public class Service{ private Collaborator collaborator; public Service(Collaborator collaborator){ this.collaborator = collaborator; } public String performService(String input){ return collaborator.transformS...

Enumerable is the most popular module in Ruby. Its purpose is to provide you with iterable methods like map, select, reduce, etc. Classes that use Enumerable include Array, Hash, Range. To use it, you have to include Enumerable and implement each. class NaturalNumbers include Enumerable de...

The core concepts of RxJava are its Observables and Subscribers. An Observable emits objects, while a Subscriber consumes them. Observable Observable is a class that implements the reactive design pattern. These Observables provide methods that allow consumers to subscribe to event changes. The ev...

Comparable is one of the most popular modules in Ruby. Its purpose is to provide with convenience comparison methods. To use it, you have to include Comparable and define the space-ship operator (<=>): class Rectangle include Comparable def initialize(a, b) @a = a @b = b ...

angular.module("app") .service("counterService", function(){ var service = { number: 0 }; return service; });

angular.module("app") // Custom services are injected just like Angular's built-in services .controller("step1Controller", ['counterService', '$scope', function(counterService, $scope) { counterService.number++; // bind to...

DELETE FROM `table_name` WHERE `field_one` = 'value_one' This will delete all rows from the table where the contents of the field_one for that row match 'value_one' The WHERE clause works in the same way as a select, so things like >, <, <> or LIKE can be used. Notice: It is necessa...

DELETE FROM table_name ; This will delete everything, all rows from the table. It is the most basic example of the syntax. It also shows that DELETE statements should really be used with extra care as they may empty a table, if the WHERE clause is omitted.

An unnamed namespace can be used to ensure names have internal linkage (can only be referred to by the current translation unit). Such a namespace is defined in the same way as any other namespace, but without the name: namespace { int foo = 42; } foo is only visible in the translation uni...

Privileges The CREATE VIEW statement requires the CREATE VIEW privilege for the view, and some privilege for each column selected by the SELECT statement. For columns used elsewhere in the SELECT statement, you must have the SELECT privilege. If the OR REPLACE clause is present, you must also have ...

Statement-level parallel hints are the easiest: SELECT /*+ PARALLEL(8) */ first_name, last_name FROM employee emp; Object-level parallel hints give more control but are more prone to errors; developers often forget to use the alias instead of the object name, or they forget to include some objec...

4.0.3 Using a CustomTabsIntent, it is now possible to configure Chrome custom tabs in order to customize key UI components in the browser that is opened from your app. This is a good alternative to using a WebView for some cases. It allows loading of a web page with an Intent, with the added abil...

In C#, there are two different kinds of equality: reference equality and value equality. Value equality is the commonly understood meaning of equality: it means that two objects contain the same values. For example, two integers with the value of 2 have value equality. Reference equality means that ...

There are few approaches available there: You can subscribe for keyboard appearance events notifications and change offset manually: //Swift 2.0+ override func viewDidLoad() { super.viewDidLoad() NSNotificationCenter.defaultCenter().addObserver(self, selector: #selector(YourVCClas...