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public class Tag { public IList<string> Synonyms { get; set; } } Synonyms is a collection-type property. When the Tag object is created using object initializer syntax, Synonyms can also be initialized with collection initializer syntax: Tag t = new Tag { Synonyms = new List&...

To read the contents to a file into a string variable: Dim fileContents As String = System.IO.File.ReadAllText("filename.txt") ReadAllText will open the specified file, read data to the end, then close the file. To read a file, separating it into an array element for each line: Dim f...

;; package.el is available since emacs 24 (require 'package) ;; Add melpa package source when using package list (add-to-list 'package-archives '("melpa" . "http://melpa.org/packages/") t) ;; Load emacs packages and activate them ;; This must come before configurations o...

In all serious Prolog systems, association lists are available to allow faster than linear access to a collection of elements. These association lists are typically based on balanced trees like AVL trees. There is a public domain library called library(assoc) that ships with many Prolog systems and ...

Consider the following block of code. try { using (var disposable = new MyDisposable()) { throw new Exception("Couldn't perform operation."); } } catch (Exception ex) { Console.WriteLine(ex.Message); } class MyDisposable : IDisposable { public vo...

6.0 Introduced in C# 6.0, the Null Conditional Operator ?. will immediately return null if the expression on its left-hand side evaluates to null, instead of throwing a NullReferenceException. If its left-hand side evaluates to a non-null value, it is treated just like a normal . operator. Note tha...

To connect to a local Wildfly server via the command line, the tool bin/jboss-cli.sh can be used: $ ./bin/jboss-cli.sh --connect [standalone@localhost:9990 /] To connect to a remote Wildfly server, use the --controller option: $ ./bin/jboss-cli.sh --connect --controller=localhost:9990 [stan...

In order to record audio from a user's microphone, we must first gain permission from the user to access the device: navigator.mediaDevices.getUserMedia({ audio: true }) .then(successCallback) .catch(failureCallback); On success, our successCallback will be called with a MediaStream ob...

Unification is a pure relation. It does not produce side effects and can be used in all directions, with either or both arguments fully or only partially instantiated. In Prolog, unification can happen explicitly, using built-in predicates like (=)/2 or unify_with_occurs_check/2 implicitly, whe...

Optionals (also known as Maybe types) are used to represent a type whose contents may or may not be present. They are implemented in C++17 as the std::optional class. For example, an object of type std::optional<int> may contain some value of type int, or it may contain no value. Optionals ar...

BEGIN TRANSACTION INSERT INTO DeletedEmployees(EmployeeID, DateDeleted, User) (SELECT 123, GetDate(), CURRENT_USER); DELETE FROM Employees WHERE EmployeeID = 123; COMMIT TRANSACTION

Prerequisites In order to run Elasticsearch, a Java Runtime Environment (JRE) is required on the machine. Elasticsearch requires Java 7 or higher and recommends Oracle JDK version 1.8.0_73. Install Oracle Java 8 sudo add-apt-repository -y ppa:webupd8team/java sudo apt-get update echo "or...

CREATE TABLE person ( person_id BIGINT NOT NULL, last_name VARCHAR(255) NOT NULL, first_name VARCHAR(255), address VARCHAR(255), city VARCHAR(255), PRIMARY KEY (person_id) ); Alternatively, you can place the PRIMARY KEY constraint directly in the column definition: ...

OrientDB is available in two editions: Community Edition is released as an open source project under the Apache 2 license. This license allows unrestricted free usage for both open source and commercial projects. Enterprise Edition is commercial software built on top of the Community Edit...

A template autorun may be used to (re)subscribe to a publication. It establishes a reactive context which is re-executed whenever any reactive data it depends on changes. In addition, an autorun always runs once (the first time it is executed). Template autoruns are normally put in an onCreated met...

CREATE FUNCTION FirstWord (@input varchar(1000)) RETURNS varchar(1000) AS BEGIN DECLARE @output varchar(1000) SET @output = SUBSTRING(@input, 0, CASE CHARINDEX(' ', @input) WHEN 0 THEN LEN(@input) + 1 ELSE CHARINDEX(' ', @input) END) RETURN @output END ...

Sometimes a term is defined in multiple sections of the manual. By default, man will only display the first page it finds, which can be annoying for programmers because C functions are documented in a later section than commands and system calls. Use the following to display all pages that match a...

Let us build a simple control, a rating widget, intended to be used as: <rating min="0" max="5" nullifier="true" ng-model="data.rating"></rating> No fancy CSS for now; this would render as: 0 1 2 3 4 5 x Clicking on a number selects that ra...

When you need to pass a collection into a Java method: import scala.collection.JavaConverters._ val scalaList = List(1, 2, 3) JavaLibrary.process(scalaList.asJava) If the Java code returns a Java collection, you can turn it into a Scala collection in a similar manner: import scala.collectio...

To create minification-safe angular controllers, you will change the controller function parameters. The second argument in the module.controller function should be passed an array, where the last parameter is the controller function, and every parameter before that is the name of each injected val...