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ActionCable was available for Rails 4.x, and was bundled into Rails 5. It allows easy use of websockets for realtime communication between server and client.

Approach with sealed trait and case objects is preferred because Scala enumeration has a few problems: Enumerations have the same type after erasure. Compiler doesn't complain about “Match is not exhaustive", if case is missed it will fail in runtime scala.MatchError: def isWeekendWith...

Snackbar make (View view, CharSequence text, int duration) Snackbar make (View view, int resId, int duration) ParameterDescriptionviewView: The view to find a parent from.textCharSequence: The text to show. Can be formatted text.resIdint: The resource id of the string resource to use. Can ...

Visual Basic 14 is the version of Visual Basic that was shipped as part of Visual Studio 2015. This version was rewritten from scratch in about 1.3 million lines of VB. Many features were added to remove common irritations and to make common coding patterns cleaner. The version number of Visual Ba...

NSDate() // NSDate object init to the current date and time NSDate().timeIntervalSince1970 // Current date and time in number of seconds from 00:00:00 UTC on 1 January 1970. NSDate().compare(other: NSDate) // Returns a comparison of current date to another date returns a NSComparisonResult ...

Set - The operator used to set a reference to an object, such as a Range For Each - The operator used to loop through every item in a collection Note that the variable names r, cell and others can be named however you like but should be named appropriately so the code is easier to underst...

You can create package.json with npm init which will ask you about basic facts about your projects, including license identifier.

AR is perfect when you need to delete, update or create one or more records sequentially. Its support of dirty attributes (saving only what was really changed) results in optimized UPDATE statements which lifts the load from database significantly and reduces chances for various conflicts connecte...

These classes are reference libraries of methods and properties that do not change state, in one word, immutable. You don't need to create them, you simply use them. Classes and methods such as these are called static classes because they are not created, destroyed, or changed.You can refer to a sta...

Android Marshmallow introduced Runtime Permission model. Permissions are categorized into two categories i.e. Normal and Dangerous Permissions. where dangerous permissions are now granted by the user at run time. From sdk 23 Android requires runtime permissions for permissions on devices runni...

AVSpeechSynthesizer() // Creates a speech synthesiser speaker.speakUtterance(speech) // Converts the text to speech ParameterDetailsspeakerAVSpeechSynthesizer objectspeechAVSpeechUtterance object

All algorithms are a list of steps to solve a problem. Each step has dependencies on some set of previous steps, or the start of the algorithm. A small problem might look like the following: This structure is called a directed acyclic graph, or DAG for short. The links between each node in ...